@dutchpilot Hi, thanks for reporting this! I will check that clock out to see what's gone wrong there, it uses the stock settings so it should be fine but maybe something got tweaked without me realising. For the DED, I will ask CodenameJack, who created it all. It's a far more complex system than is in the real jet in terms of autopilot ( more like an airliner than is necessary really ). The manual was recently updated with his instructions for use, so if this isn't in there I will have to find out and update it.
As far as I know, TACAN is not yet supported in MSFS but I'm pretty sure I have seen others figuring out a way to get it. It's something that I will add to all of my jets going forward, along with some other cool extras like radar.