How to reload tablet drivers for X61T?

[atanasoff]

The tablet functions for my X61T ceased to work properly after a W7 to W10 upgrade (the thing auto-started, couldn't cancel it) and rollback some time ago. It's now more-or-less-mostly working in W7, but the tablet functions are not all there.

How do I reload those? I do not have the original install disks, and the recovery partition appears to be empty. Pardon if this is a basic question, I didn't find the procedure via search here.