Thank you for suggesting that. I managed to get 3D Coat working smoothly with my tablet again but the solution I used was one or all of the following:
1: uninstall my driver for the Huion pen (using their latest version still) completely making sure to clean up with CCleaner before reinstalling it because something weird was going on with it not uninstalling properly first. Restart the computer and reinstall it. That didn't solve the 3D Coat problem, but I probably needed to do it anyway.
2: Don't know if it could be related- probably not but I updated my computer Bios and made sure things were all OK with the computer regarding drivers etc... still had the 3D Coat problem, but I think it sped my computer up a bit and fixed some audio problems I was having.
3: I think my copy might have got corrupted the other day because I had tried the automatic updater but it froze on me, then I had had to uninstall and reinstall it but then I had these weird lag problems I wasn't having before (in paint and the sculpt room). I had also moved the default location of the resource folder to a different drive, same as the program is installed to- don't know if that was related or not, but worth saying just in case.
So I uninstalled my copy of 3D Coat and ran CCleaner tool to make sure it was all gone, deleted traces of it in the user appdata and documents etc... downloaded the latest stable version off your website and reinstalled it using my admin account last night.
This morning I ran 3D Coat using my work account (I use a limited user account on Win 10 for my work) and it works fine again! Problem solved. Just writing this here in case it helps anyone else.
All the best
Christine