JCL,

How do we overwrite this? If I'm trading a 100K account, I'm getting lot sizes as low as 0.03

Changing the assets.dta gets overwritten, as you said, but playing with the sliders doesn't seem to change much at all.
The setting of LotSize doesn't seem right at all for larger accounts.

A quick fix would be to add a Multiplier variable to the MT4 side of things so that accurate real lotsizes could be set.

Regards,
Merlin