I bought Winstep Xtreme a few months ago and like it a lot.
While playing around with it, I did find a few bugs (at least I think they are, but maybe I have some wrong settings) which I would like to report:

In Dock Properties I have checked the box 'Respect space reserved by other docks, toolbars and screen objects'.

However, I found two examples for this not being obeyed.

First example is shown in attached screenshot Overlapping_docks.jpg.
In this case the second subdock opened from the bottom dock interferes with the dock on the right, while there seems to be sufficent (empty) space on the left side of this subdock. So, why is not shifted to the left?

Second example, more serious, is shown in the attached figures Before-opening-1.jpg and After-opening-1.jpg. In the situation shown in Before-opening-1.jpg, I opened the subdock by clicking on the right most Nexus icon. I expected the subdock to be opened on top of the parent subdock, but instead it opens below the parent subdock covering the first opened subdock.

Hope you can look into this and provide a solution (especially the one mentioned in the second example).

For some reason attaching the screenshots did not work (I used upload attachment). Is this not allowed on this forum?

Link to pictures:
Overlapping-docks.jpg: http://i45.tinypic.com/2a7g5tx.jpg
Before-opening-1.jpg: http://i50.tinypic.com/rho4fd.jpg
After-opening-1.jpg: http://i50.tinypic.com/1693qfc.jpg

The 'respect screen space reserved by other docks and toolbars' is a setting specific to docks, not sub-docks. Sub-docks will behave differently since they are only supposed to be open for a short time.

The option to open sub-docks NOT perpendicular to the parent dock was also only added recently, so it's natural to have some minor glitches like that one that still need to be ironed out.

As for your second issue, it is related to the reason above, the dock is still thinking in terms of vertical/perpendicular sub-docks when deciding where to open one. Vertical sub-docks would always open in the direction where there is more room on the screen in order to maximize the number of icons displayed (e.g.; in the first screenshot, there is more room available above the first sub-dock than below it - however, for the second sub-dock that is no longer true, so the third sub-dock opens below it, overlapping the first sub-dock).

Hope this makes sense.