Glad you were able to get it set up. For my own question, are you using 64 bit amibroker ?
a. from my understanding and reading the documentation there is no backfill capability using DDE link. But I suppose that going forward you will build historical data for each specific ticker.
b. I believe that if TOS is set to realtime than amibroker will also receive the infomation from TOS. Did you make sure that TOS is realtime data feed ? I had to get in touch with support and have them turn it on. Does it show realtime in the upper left corner?