DSB Northrop F-20 Tigershark

Just got into Flight Sim this year after after scrimping and saving enough to finally get a PC fast enough to handle it (Windows Vista Home Premium 64 bit, 2.5GHz, 4 GB RAM). Really a kick! I went through all the lessons (had a private license back in the 60s), and got into most of the FS9 planes. The one I like the most was the default Lear45.Since I wanted to try something different, I recently downloaded a half dozen freeware models for FS9, and the DSB Northrop F-20 Tigershark turned out to be the one that I really liked. It appeared to be easy to fly, and it was the only recently downloaded model whose autopilot really worked.However, I did have problems with it: 1. The HDG and CRS would only increment by 10. My local airport uses a CRS of 258 for it ILS, and I found several more airports like this. Fortunately, the F-20 was still able to use the ILS, but it requires several manual corrections to stay on course. I tried to correct the xml file, but it looked like this was an error with MS FS2004 code, not with the xml file. 2. While trying to set NAV1 to my local ILS frequency of 109.9, I found that the program would only increment/decrement in KHz this way: 25, 30, 35, 30, 45, 50.....80, 85, 80, 95, 00. There was no way I could set 109.90. This again appeared to be a Microsoft error. So, I installed a radio panel from the Lear45 default. This worked perfectly. 3. Today, I discovered that I cannot get the speed over about 300 knots, and that the AP is faulty. Won't hold ALT or IAS. Could only shut off AP completely to bring it under control, then the speed started falling off even through the throttle was full on, until the F-20 crashed.My question is... Has anybody found corrections to these problems? I certainly would have been upset with Iris software if I had paid for faulty software.