TierTime Inspir D290 (or GII) and S250 related problems

Hi friends.
I think we are one of the oldest customers of TierTime.
We have some problems with our D290-s and s250 printers.
one of these problems in D290 (or GII) 3drpinters is “removing the support” from the main part
According to our experience through these years we found that although D290 (and S250) printes are dual extruder , but it is better to use the printers as single Nozzle (which can be set in ModelWizard software).So within these years we always use single nozzle printing but sometime we have the problem of very bad sticking of support to main part . specially in slopped and curves (not parallel with platform) surfaces. In the same time if we print the same part with S250 (still single nozzle) or Up , the support is removed easily .
As I check different reasons , I think it does not depend to platform z value (I mean the z value of head at start) but I think it depends on temperature value , can any body help me?

thank you
In the same time ,