I'm running Start8 with Windowblinds 7.91 and have been running these two since they both became available -- and do not have those problems with Start8. I'm using the Sublime skin -- but have used other skins that were installed by default with Windowblinds 7.90 and didn't notice any problem with those, either.
Have you tried looking at the Fonts settings in the Windowblinds theme you're using?