Really? Can you elaborate? Because that would be an issue for me.
The way a computer talks to it is basically through a type of 'printer' driver. Windows literally thinks it's a printer. It's not far from the truth, though, so it's not crazy to think of it like that. So you have to have a driver installed. At one time, it was running on a Windows XP machine. When XP was no longer supported/updated, we upgraded all computers to Windows 7. The driver no longer worked. They did not have a Windows 7 driver available on their website. We couldn't get it to work even using some of the built in 'compatibility mode' tools. Our IT was stumped for quite a while. We could not get anyone at Epilog to call us back, talk to us at all, nor answer emails or anything. Our IT guy finally figured out some sort of hack to get the XP driver to work. We limped along with that for a while though performance certainly suffered (large file sizes would often time out and fail. So we could use 'color mapping' much less frequently, or for smaller parts or fewer parts)
We had to limp for quite a long time before they released a driver that worked for Windows, and they never bothered to tell us about it. One day our new IT guy decided to call them up and see if he could tackle it, and their tech sent him their driver as they were getting ready to put it on the website.
It was several YEARS that Windows 7 had been out and in common usage before they had a driver for it... and it was well after XP support was discontinued by Microsoft. I found that simply ludicrous.
Otherwise it "just works" - don't worry about the machine itself. Clean the lens now and then. I use denatured alcohol and cotton swabs, following up with alcohol-dosed non-linting cloths. I do it like.. once a year. Depends on your environment. We cut a shit load of cardboard stencils for painting crates and sometimes dies and large tooling. The fumes/soot from that probably makes it worse for us.
We did have to replace a board in there once. It was basically a "it's broke and we have no idea how/what/why" and we couldn't get in touch with Epilog to troubleshoot it. Our maintenance guy COULD, however, get parts, so we just solved it with the heavy handed approach. It worked. AFAIK that's the only maintenance we've done. The only other thing we've done is the occasionally belt tightening.
The table will never stay perfectly square to the laser movement, and it'll move over time. There's a bar screwed to the table along the X-axis. I have a second bar sitting loose in front of that. One end has a .094 drill between it to 'shim' the bar out at an angle. Every few days we'll check the laser (by scanning the red dot along the edge of the adjustable bar) I'll slide the drill left/right as needed to finely adjust the angle until the red dot tracks perfectly-enough along the edge.
That basically sums up any problems or 'issues' we have. There's nothing hard to work around, and it's good enough for what we use it for. I only have to use that 'adjustable bar' to fix alignment because sometimes .010" makes the difference between good gold-plated parts .. and parts that now need to have the etching sanded off, and re-plated.