You can download not only the manual but the entire program as a 30 day free trial. There are some limitations but you'll get a good idea of the program's capabilities.
Slice and cuts can be frame accurate -- just zoom in. Note: edits are 'non destructive' if you change you mind just drag out the cut end to restore.
I'd definitely recommend the Plus or Premium version. The extras are well worth it!
C:\Program Files\MAGIX\Movie Edit Pro Premium\2017
for Videodeluxe_EN.pdf
Look at pages 104 to 106 for trimming objects. Other than what Carl indicated, there is an Object trimmer and a Cut trimmer (for transitions), which give you frame by frame access for trimming, fading and transitions.
Once you purchase the program, there is a lot more to download.
As Carl says, go for Plus or Premium, as basic is just too limited.