Skipping when trials are randomized?

[EBT]

Hello,
I am experiencing a similar problem. In my case it is not the video that needs to be randomized, but the question order. I have the same video on several trials, and those trials need to be randomized. However, the trials also need to be paired - 2 by 2. For example:
Trials 1a, 1b, 2a, 2b, 3a, 3b -> 1b should always follow 1a, 2b should always follow 2a, etc. But the order of 1, 2, and 3 should be randomized.
Is there a way of linking the a and b trials?
Under different circumstances I would use the BGR, but in this case I need that to group questions related to different videos - the overall structure is this: Several videos, each associated with a group of questions, and the questiones need to come in pairs. The video blocks need to be randomized, and the questions within the blocks need to be randomized too (keeping the pairing though).
The only solution that comes to mind is to create a separate .que file for each video, and then randomize the .que files within the .exp file...
Thanks in advance!