Thanks! It has taken a few hundred hours of labor intensive programming to get this far. But it has been an exciting journey of discovery. I'm also writing an Instructions PDF to describe all the various Program Menus and Features like Paolone does with Icaros and another PDF called Programming ShowPicture which will illustrate the techniques used and how they came about. As soon as the PDF's are done and I have finished Icon support which is about 90% done, I will post the first version of ShowPicture for everyone.
I have decided that ShowPicture is NOT a paint program. Rather it's a Graphics Processing Program. We don't paint directly to pixels on screen. We manipulate all the pixels and transform them into something else. It involves a lot of Formulas, Specialized Algorithms, and Mathematics and some Color Theory mixed in.
Given the choice of doing things the easy way or a more difficult and more unconventional way that would yield superior results, I would choose the hard way! It's more rewarding in the end.
The many possibilities while using the Colorize Effect as with the colored icon images in the sample are evident. Colorize can be a powerful tool. I could do it the easy way and just process one Color Group transformation at a time, or I could do it the hard way and allow multiple transformations. I'll do it the hard way.

An image such as these samples can have one or multiple Color Groups. The original Drawer Icon has a single Blue Color Group. The hues are inthe Range of 210 to 240 degrees on the HSL Color Wheel. So, how would we process multiple Color Groups simultaneously, pushing our CPU's and GPU's to the max? I will scan the image and sample pixels using 12 predefined Color Buckets to determine Color Groups the display a Color Selector with up to 12 groups on top represented by colored Squares. The bottom 12 slots will be empty so the user can choose destination colors for each Color Group in the image. Then we could process 12 groups at a time. That's a lot of pixel operations! It should take a few seconds.
Doing things the hard way also applies to a Colorful About Box. I'll give you an idea of what I'm planning. Most programs and AROS libraries that use icons only look for one or two png images. ShowPicture has a special App Icon that has three png images. The third png is a 100x100 app image. I might use bit fields and some creative masking for special effects.
Happy Coding!