now my trial period is almost over and I did not manage to create any single render which would be even close to my expectations

I don't make the mistake of blaming that on LU because I know that I am not able to use this tool properly.
I still don't understand the tool´s concept - despite of tutorials and forum´s help etc. Maybe I can't find the right or recent tuts or intros to find an appropriate access into LU.
- I wait forever until i see any bulky result on the screen
- I don't get to see the material editor when i double click on a material - at least in 95% of the cases does LU react so slow?
- I run several very powerful equipped computers but it's all so slow and in half of the cases, my entire machinery gets stuck.
- the triggering of the tour tool button does not cause a reaction anymore then
- the tour-tool opening of a slightly larger model (and my models aren't really big) takes an eternity
- besides all these inhibitions, i didn't even find the opportunity to test interior artificial lighting or the cool AO features
or even go for a walk in the rendered model
- why does LU occupy every new SU model with the light material-icons in the SU´s material window, regardless of whether one uses LU or not?
So my trial summary unfortunately is quite frustrating - all the more so as I see that other people come clear with great results...
btw
- thanks for the really long trial period which is not stingy at all! (but in which it would be good to avoid the watermarking as a suggestion)