I have an account with Stage5 and have been trying to move my NT7 setup to OEC. In order to do that I have been looking at the need to program a couple of things for OEC.
OEC is not truly an EasyLanguage platform. Without a working Tradestation platform it is not possible for an OEC user to take advantage of EasyLanguage indicators that are in .eld format. OEC cannot read .ELD files. It can compile some EasyLanguage files if they are saved as text files, .el for example. OEC does this by interpreting it's own catalog of EasyLanguage syntax, keywords and functions and then compiling that interpretation.
OEC's native system is OEC.net and robust and maintainable indicators need to be written using that system.
While I do not have a good knowledge of object oriented programming, C# or .NET, I have been very successful in writing indicators for Ninjatrader. This is because there is a high level of support for ninjascript, especially here at futures.io (formerly BMT), thanks.
I have no idea how popular OEC is but I am casting my vote for a separate spot in futures.io (formerly BMT) for OEC programming.