if you already have bought the game from managames.com , then get your Steam Key to try out the Beta version of TE2013 on Steam from here : http://www.managames.com/Key_en.php
You need to sign in through Steam 1st (by clicking on the Green Steam icon), then enter your Customer ID, and if you got a new email address since you bought the game, then also enter your email address.
You'll then receive your License Key email with your Steam Key in it.Warning:
you can ask your License Key to be resent only once per day, so be sure to sign in through Steam 1st, else you won't get your Steam Key on 1st try, and double-check your email address.
Asking you to sign in through Steam 1st was the only way to connect your current online account to your Steam account, so you'll keep your ELO, number of played games, reputation, etc... You can swap between the Steam version and the MG version without problem, your account info should always stay the same.
If you have lost your Customer ID, then the 1st step is to request your License Key email to be resent. It can be done only to the email address you used during your order. Then the following day, you'll be able to request your Steam Key using your Customer ID from the License Key email.
Right now, there are only 99 Keys left, I called dibs on 1st one..!
The current version lacks achievements, I'll be working on them next week.
If you can try out the Cloud saving, let me know, I'm not sure if it's working or not.
If you'd like to to be able to connect directly (ie: using Steam interface) to an online game hosted by a friend, let me know. I may be able to add this functionality, but before to spend time on it, I'd like to be sure it'll be frequently used.