hmm, I was using a single jetway at the gate I was testing, I can't imagine it would have something to do with the Default 747 either, but I'm definitely seeing a difference in stability between small/medium and heavy gates. Fortunately, I don't fly heavies that often, this time I mainly wanted to put GSX:L2 through it's paces.
I'm sure part of the problem is that every addon uses simconnect these days, almost nothing uses FSUIPC anymore, or if it does, it uses both similtaniously
, and it's hard to keep FSX running well without some of these addons now.