We still have to find out why the download has this issues in the newer versions.
My trading approach is based on Zorro 2.70 (64bit FXCM Plugin) and the failing lockback issue is still blocking me.

We have now tried to reproduce your observations and downloaded many MB in 32 and 64 bit mode from FXCM, but did not see any gaps or other problems. The FXCM server was as reliable as usual.

Maybe an unreliable Internet connection caused the problem. Or the FXCM server had an issue last week which was now solved.

Please get the latest release candidate 3.01.1 from the download page and run the following script in both modes:

function main()
{
Verbose = 15;
set(LOGFILE);
NumYears = 10;
assetHistory("GER30",1+OVERRIDE);
}

Then please send us the log and diag.txt.

I will do the test, but my Zorro S subscription was ending with 2.70. My setup (framework of many .cpp 64bit files + Python Gui) is running with Zorro-S functionalities. I had my errors in the beginning via trading (missing historical data during the LookBack), but then I recognised the gaps during the loading (Download script) of historical data.

Therefore, I have to test with the Zorro Free account, but I will do. I will use your script.

Martin