Sundance: Yes, it was your session. The CSV file shows a low margin in Janurary, than a high margin until about March 30, then again a low margin. It looks as if the Margin slider had been temporarily moved. But we can not see from the file what the reason was. We're running about 20 trading Zorros since 2 years, but have not experienced any margin issues, except of course when the slider was intentionally moved.
Maybe we can learn more when other people report the same issue - that's why I opened the thread here.
Thus, we can not give a real recommendation at this point. It could be an accidental, unnoticed click on the slider - in that case it was a unique problem and won't happen again. Anyway reinstalling Zorro would not help here.
Two suggestions. For making sure that Margin is not accidentally set to a high value, you can limit the margin in the .ini file. Of course this has the disadvantage that you have to stop and restart when you want to increase the margin.
Second suggestion: Use Excel to look into a copy of the .csv file from time to time. You can do that while trading. Check the "Lots" column. All trades of the same type should have about the same number of lots. If there is a huge difference although you have not moved the Margin slider, something is wrong.