Problems 2 and 3 are most likely caused by a faulty MUI setup. Does the MUI Prefs program work?
When you re-install MUI v3.8, make sure you also delete the settings in Envarc:mui first.
Add only external classes that the programs really need, to avoid cluttering.
E.g. NList, Betterstring, Texteditor.mcc.
When installing, choose Expert mode and create Protocol file.
That way you get more decisions to make instead of libraries and such get overwritten without warning.
As your system is already setup for you, there is the possibility of mismatch regarding your CPU or FPU, e.g. Libraries, MMU settings and what not.
