adding groups & new files not working (pro Version 1.6.1 )

just bought the pro plugin – installed as normal on 3.8

trying to add a user group i get “Please fill out the form” – what form ?

trying to add a new file i get a blank page at xyz.com/cmdownload/add/ –

i can get to /cmdownload/dashboard/

but when i click on the “add new” i get back again to the empty cmdownload/add/

permalinks are set to post name

docs for a paid plugin are non-existent

not impressed so far

https://www.ads-software.com/plugins/cm-download-manager/