Hi Frederick,
There's no generic incompatibility between UpdraftPlus and W3 Total Cache that I know of - a previous version of W3 Total Cache had problems with its object cache on scheduled tasks (which affected all backup runs), but I believe you fixed that in the latest version?
Daniel - if you want to work through the problem you had causing a blank screen with W3 Total Cache on your site, then please open that as a new forum post in the W3 Total Cache forum (i.e. not in the UpdraftPlus forum). If you open it in the UpdraftPlus forum then it sends me an email alert every time there's a post, which will just be spam for me if you're pursuing a W3 Total Cache problem.
Best wishes,
David