Getting the fonts to look acceptable on Mac OS X Snow Leopard requires too many manual changes and too much trial and error to consider this issue resolved from a customer perspective. SlickEdit should provide something that guides the customer through the steps necessary to improve the font quality. Or, the SlickEdit install on Mac OS X should do these steps automatically.
Please note too that not all fonts look acceptable even after making the changes I describe in my earlier post. Inside the SlickEdit options dialog, I went through every installed font before settling on Helvetica [Adobe] as my proportional font of choice for the Menu and the Dialog. Attached is a screen shot that shows what a not so good font looks like (Bitstream Vera Sans at 9 pt).