What steps will reproduce the problem? 1.select some pixels
2.attempt to add another individual pixel to the selection that is near one of the hulls in the marquee tool What is the expected output? What do you see instead? I would expect to be able to expand (or de-select) a given pixel without experiencing interference from the current selection. At the moment if the cursor is too close to one of the 8 points in the marquee tool you may find that the mouse would rather let you scale or rotate the selection instead of allowing you to add or remove pixels from the selection. What version of the product are you using? On what operating system? Windows 7 x64 v0.9.5 Maybe it would make more sense to use a modifier key (shift/alt) when in marquee mode to expand or contract a selection rather than using the left/right mouse buttons? this way, it could trigger a change in the behavior of the marquis tool to not force a scaling/rotating behaviour.
I'd also appreciate it if there could be universal add/remove from selection with the shift/alt key combination for all selection modes- meaning magic-wand too. Rather than having to click the [+] or [-] buttons at the top of the work area.
A "paint selection" option would also be extremely helpful- where it uses the current pencil size to select/deselect, so you could easily just "draw" minor selection additions rather than trying to lasso it.
The current default behavior (as in v1.0) is the most MS Paint-like behavior, which I think is quite useful and handy (and familiar?) most of the time. So we don't have to lost this flexibility.
Anyway, it looks like having scale/rotate handles visible/enabled all the time is not friendly in some situations. There is another related issue to this one ( issue #370 ) to show the rotation pivot by default, I think that we need a button/configuration in the context bar to switch the visibility of all transformation handles by default.
I will try to add some keyboard modifiers to enable those "universal" add/remove selection modes. Something similar to Photoshop.
About the "paint selection", it's already possible configuring it in the section of gui.xml (anyway it's too internal stuff). There were an intermediate beta version that included a special ink mode for any tool to paint selection with any tool. I've to figure out how to make this accessible in a easy way (an "Advanced" button for sure).