no idea I'm using 4.6.4

It could simply be that it's running in 'idiot' mode (simple)
Try setting it to run in 'not-an-idiot' mode (advanced).

Pretty sure it hasn't asked me if i want to update recently.
So maybe 5 is aimed at some of the newer machines specifically ?

Or it could just be in idiot mode.
Flashprint is my second favourite slicer - so can;t see why they'd bugger it up. never have in the past.

I#ll go see if i can find it.