I've run into this problem repeatedly with Avenger and Mongoose products.
Mongoose have done their best to sort out what can and can't be done, but then the goalposts have a way of getting moved at the approval stage. This tends to happen because Marc is surrounded by a bunch of fanboys who have their own agenda, and he's willing to let them influence his decisions - even decisions already made.
For example, the Living Traveller campaign... Mongoose agreed with Marc that I could play fast and loose with some aspects of canon. I did an outline, and it came back with a series of sarcastic and rude vetoes all over it.
When I protested, I was told by the Marc-end of the process that these 'vetoes', which came from Marc as if written by him, were actually written by Don McKinney, his fanboy-in-chief, and were, in Don's words 'flagged issues' and not vetoes at all. I was also told that his scarcasm and rudeness was just how he writes.
In short, I received back a document that, metaphorically speaking, looked like it had 'are you f**king stupid? No, NO, NO!' scrawled all over it by Marc Miller, but was actually supposed to be a list of 'issues that might need discussion' written by someone else.
More importantly, Marc had let Don do this, speaking for him with his blessing, but had not told Don that Marc and I had agreed that I had considerable leeway when interpreting canon, and could even make fixes or changes where it seemed like a good idea.
So... Marc agreed what could be done, then handed over to a fanboy rather than make the decisions himself, effectively ignoring the agreement he'd made with me/Mongoose about how to treat canon.
This is why I handed back the Living Traveller campaign.
It's not an isolated incident; in fact this sort of thing happened several times, eventually resulting in me deciding that it wasn't possible to work under these conditions.
I tried repeatedly to fix the problem; that tended to result in promises to sort it out, but nothing ever changed. After repeated attempts I gave up on OTU Traveller stuff that had to go through this painful process.