As mentioned previously, we have not distributed anything, nor do we allow games to be taken away from RCM for any reason. They are for playing on site only.
I will bring Andy's attention to this as to how RCM would like to proceed concerning the one game in question ("Deathstrike").
As a side note, I would like to personally disagree with you on the concept of "Abandonware". While you are technically correct from a legal point of view, I don't think it's ever been asserted (not by respectable parties at least) that "abandonware" is "copyright free". Rather, abandonware covers software which is so old that the copyright owner has (or would have) little to no interest in pursuing copyright claims on it.
To wit, the majority of ZX Spectrum games publishers have waived their copyright to said games on the grounds that their is no commercial merit in the legal costs of enforcing it, even though legally they still have a right to do so.
Similarly, it can hardly be said that the Sinclair QL is a "booming games industry" - it was hardly that when the machine was current. Thus (while respecting your copyrights in this matter) your, shall we say, firm hand in a computer museum's use of QL games (again, *NOT* distributing) seems a little over the top if you don't mind me saying.