Rick your file was saved in Indexed Color mode ... not CMYK and which is not native to either the BMP format you used or JPG. What application are you using to save these files? JPG is best because the site software handles it well and will generate a thumbnail. Using BMP requires anyone wanting to view the file to actually download it and then open it. You're causing others extra work and probably losing half the members that might otherwise be willing to help.
You list Flexi and Corel in your software lineup. Either one will easily generate an RGB JPG.