The problem with the data upload limit for attachments has been fixed. I have restored it to 30MegaBytes. A recent forum software upgrade was responsible for the changed limit. Please accept my apologies for missing this when upgrading the forum sofware, Mabula.
Undo / Redo dropdown in the Tools menu
I've been using APP for a a little over a month now and I'm really impressed at the results that I'm getting. In fact, with time I've found that a lot of features that I thought were missing can simply be done differently in APP. For example, a slight adjustment of the HL slider is great at preventing stars from getting overstretched. With practice I've been able to get great results with the remove light pollution as well as the calibrate star colours tool. However It would be much easier to be able to undo a setting to compare before and after versions of the image. Is this something that could be added to the dropdown image viewer window?
Keep up the good work!