ok, so not grayscale at all, just kid of grayed. Are you using the Dark theme or the System theme? There is code to adjust bitmap palettes when the image is loaded to compensate for darker and lighter backgrounds. This is necessary because the same bitmap might look great on a dark background and terrible on a light background. If you try to "leave it alone" you will ultimately have bitmaps that don't really "pop" in either case. You can force this code when loading a color bitmap by append "@d" (dark background, image will be brightened) or "@l" (light background, image will be darkened) to the end of the file name "_bh_workspace.ico@d", for example.
Knowing that some people might want more muted colors, and others more vibrant colors, there is an advanced setting we put together a setting to bias the colors when images are loaded, however, it only applies to our bitmaps, not user-loaded bitmaps. The setting is (Macro > Set Macro Variable... > def_toolbar_pic_hsv_bias). Here are the docs on this setting:
// Hue, Saturation, and Brightness bias.
// Use this to calibrate button bar and tool window icon loading to
// your tastes with respect to color saturation and brightness.
//
// This is a triplet of "h s v", wher:
// h -- is the hue adjustment, the number of degrees to rotate on the
// HSV color wheel (ranging between -359 ... 359)
// s -- saturation adjustment (ranging between -255 ... 255)
// v -- brightness value adjustment (ranging between -255 ... 255)
//
_str def_toolbar_pic_hsv_bias="";
I was using it with the setting "-2 30 40" to make the color bitmaps pop a bit more on my old monitor.
For what it's worth, the bitmap you gave as an example looks a lot like _f_workspace.svg and bbworkspace.svg. You might want to just use those instead for consistency. I realize you have other bitmaps though, which I do not know if you are using on toolbars or in tree controls or in some other way.
