@larsbrubaker Thanks for the tip and the link, I'll let you know how it goes.

I did find the previous versions of Matter Control and started with 1.3.0 but got no response from the laptop after double clicking the executable. The laptop is an old HP Pavilion dv2500 dual processor X86 based pc. It will run Slic3r but not PrusaSlicer win32, it will run Pronterface 1.6.0 but nothing newer. My somewhat stock Ender-3 is currently connected to my fairly new HP 64-bit desktop pc. I love using MC and have been experimenting with PrusaSlicer, TinkerCAD and FreeCAD but I feel most comfortable with MC. When my desktop is tied up with a long print job I would like to be able to work on other designs, on the laptop, if I can get Matter Control to run. The last update of Windows Vista was in mid 2020 and it will not accept any more updates. I attempted to load Service Pack 1 but it would not download. Is Matter Control compatible with 32 bit PC's or does it even care?

I've spent the last few hours, without any success, on this site and on GitHub for an archive of previous versions of Matter Control. I have an old laptop running Windows Vista that I would like to put the software onto so that I can continue design work on while my PC is printing. I tried to install the current version (I was fairly sure it wouldn't work) but nothing happened. I at least thought I'd get some errors, but all I got was nothing. Is there a version that would work, and if so, where would I find it? TIA

@cope413 First of all, thanks to everyone for responding. So, from what I can tell, the G-code I typed in my earlier reply should work, as you all have explained, just fine. I do see that the M-code (M76) is left in on the first line of the Pause G-code section, so I assume that I should leave M75 in the Resume G-code section as well. Can't wait to give it a try.

@tinken If I use the "Pause At Layer" method as Lars suggests (for me it would be layer 36) what can I expect the print head to do? Will it move out of the way or just remain where it was at when it was paused? The documentation I've been able to find doesn't really say. Thanks for your help.

@larsbrubaker If I understand you and Tinken correctly, I would go to Print>....Advanced>....Layers(s) To Pause>.... and then enter, in my case, 37 and it should pause at layer 36. After this is done I would go to Printer>....G-code>....Pause G-code>.... and enter

G91 ; to pause the print
G1 Z20 E-5.0 ; move print head to Z20 and retract extrude -5 (I went with Z20 to give myself a little more room).
G90

(This is the point where I would place the hex nut into the recess)

And in Resume G-code>...enter

G91 ;resume print
G1 Z-20 E5.5 F1800 ; move print head back to Z-20
G90

If everything works correctly the printer should automatically pause at the end of layer 36 and move up 20mm to give me enough room to drop in the nut. Then when I click on Resume in the print window it should take off as if nothing had happened (in theory). Is my understanding of all this correct?

I've been using Matter Control for about a year now and still learning. I have been experimenting with other slicers lately, mostly PrusaSlicer, to explore their capabilities. Specifically, I'm trying to figure out how to pause my printer (I have an Ender 3 with an SKR mini E3 V2 motherboard running Marlin 2.0) so that I can insert a hex nut into a recess in the object, and then resume printing. PrusaSlicer allows for G-code to be inserted at a specific layer that will pause the print, move the hot-end out of the way so the hex nut can be dropped in, and then resume printing. I have searched the forum but most of the posts are about 5 years old and didn't go into a lot of detail. I know that there is a Pause & Resume button but how do I move the head out of the way? I saw the G-code tab in the printer section but I'm unsure of what codes to enter. On the PrusaSlicer forum I learned how to insert the commands into my G-code file, which I then imported into Matter Control. Everything looked fine until I raised the layer slider to the point where I inserted the extra code (basically, pause....move...let me drop in the nut...make sure the extruder is at temp...move back...resume) . The previewer went from looking normal to very dark (I could still see the object but just barely) and the object height continued to increase as I moved the slider to the final layer. I have not tried to print the G-code file yet to see if it would even work. I would like to learn how to do this within Matter Control if it is at all possible.

@cope413 I recently started experimenting with PrusaSlicer and I noticed that my Ender 3 is printing a lot faster. I had shown these pictures to a couple of folks that I have purchased 3D printed products from and they basically said the same thing you did. I just looked at the settings in PrusaSlicer and first layer speed is set at 30mm/s and the first layer height is 0.35mm. For reference, the same settings in M/C are 20mm/s and .20mm respectively. I wanted to try PrusaSlicer because James Fewster, who prints commercially, had high praise for it. One of the things I noticed is that an STL file exported by M/C and then imported into PrusaSlicer reports the there are various errors that need to be fixed (which it does). I re-slice and export the file as Gcode, then open that Gcode in Matter Control and print it (a bit involved I admit). It seemed that, overall, I was getting better prints, except when there was a large first layer surface area as in this item. Based on your suggestions I think I will go back to this single layer test print with the slower and lower settings and see if it makes a difference. As to your second point, I do thoroughly clean the build plate with IPA between each print (looking for fingerprints) and they are generally stuck on there pretty good. Thank you for your response.

I've had my Ender-3 for a little over a year and have been using Matter Control for about 8 months. That being said I still consider myself a novice because I've only been printing in earnest for the last month or so. Most of my projects have been small but I have noticed the occasional missing line (short segments) of filament and I kind of ignored it because for me it was more cosmetic than anything. Today I tried to print something bigger and important (for a project I'm working on) and you can see the areas where consecutive runs of filament aren't bonding together and started to curl up away from the print bed. I think (because I'm still very new at this) that this is under-extrusion but I'm not sure. If it is, what would be the best way to address it? I'm using Overture PLA+ with the hot end at 215 and the bed at 65. I haven't really had problems with adhesion until now (I have a glass bed and I've been happy with it), but I would like to get this figured out. I was able to finish this print but the face, which is usually smooth as glass, looks a little chewed up. I appreciate any insight you all may have.