Hello,
Unfortunately your plugin is not what I wanted for the following reasons:
Your plugin provided the range of numbers from -1 to 1, while I need the range from 0 to 1.
I have a selected part with transparent background. Your plugin tried to position the entire colored (non-transparent) part relative to the selected area (and if the colored part reaches the border of the selected area then it stops moving, regardless of how far I continue to drag the slider). What I truly need is to center the midpoint of the selected area (regardless of how much of it is transparent) relative to the entire canvas.
With your plugin, if the colored part reaches the border of the selected area, then regardless of the fact that I continue to drag the slider, the object stops moving. I would need my object to continue moving, even if it goes outside the canvas.
I am having trouble installing xod's Align+, as I can't find the mentioned two OptionBasedLibrary v0.7.9 files in the attachment.