Use the latest Ambient. If you don't like it you can always use ScalOS, DOpus5 (with the patch to view PNG icons) or WorkBench3.9 (thanks to Elena Novaretti it's not very difficult. You'll have to patch workbench.library).
Try the latest Ambient, IMHO it's great but if you don't like it install the old good WB3.9 with the Elena Novaretti patches and tools.
BTW, the ModeEdit crashes are very rare, I have never made it lock up.
Do you use a Peg1 or a Peg2?
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