Technically GSTrader is SR lite and GSTrader Pro is SR pro. The subtle difference is that all GSTrader and STrategy Runner demo's are the Pro version.
Now, the version, currently we are only offering the older versions because 99.99% of the glitches have been worked out. We'll be able to offer the new version once they have worked out a majority of the glitches for it.
Either platform is not really a Strategy Building platform, but more of a Strategy Running platform, please forgive the lame joke. But if you can program in c++ or langauges like that, then you should be able to download the api and build directly to them. Also if you can program in excel, you should be able to link the two so excel gets the price feed from SR and can send orders to SR.