Ok, it is possible. I solved my problem by adding

if(Asset == "NAS100") return(".USTECHCash");
if(Asset == "SPX500") return(".US500Cash");
if(Asset == "US30") return(".US30Cash");
if(Asset == "GER30") return(".DE30Cash");
if(Asset == "UK100") return(".UK100Cash");

at line 68 in the MQL4 file right under "string assetFix(string Asset)