It came up recently that while the Simulator in Designer should be 100%
match to the engine, it is not.

(DN's in engine start with \TREE\O\OU\Geoffc whereas in Simulator they
start with O\OU\Geoffc).

There was a fun bug with $Variable$ expansion in a Replace All token,
where IDM 3.61 engine did one thing, 4.0 engine fixed it and did
something else, so you got inconsistent results depending on your
version of Designer since it seems to use the engine JAR's to do the

Anyone else have other examples?

If there are sufficient numbers, might be worth agitating for getting
them fixed...