I'm thinking through potential issues, so bear with me. (also what version of OOTP are you on currently?)
- You have the same issue as the online guys above, which right now, appears that it could be OOTP itself and unrelated to the template. I'm not saying that is it, just that there's that possibility, especially since we're not 100% certain what is causing their issue.
- I was going to say that you might have a slightly misnamed folder or XML file. However, I've tried this and the game pretty clearly states that it can't find the file or that the parser cannot find the file. So that's not it.
- I took a game that I just installed on my computer and took a file from an online league that I am in (happen to have commish rights). I "installed" the 1974 Topps templates and it worked off the bat.
- I confirmed the inability for a non-commish in an online league to create cards. Turning off the commish flag came up with no card generated.
- Enable Baseball cards does what it should - deselecting this option removes the option from the Player Picture menu.
- Picture Search mode doesn't affect this. Works regardless of what you've selected.
- I've tried all the above on both 11.2.15 and 11.2.18 and cards always generated, either with the default template or the 1974 Topps template.
- I disabled the online league functionality and took off the Commish setting from my user. It generated the cards successfully.
- Disabling other options, such as Importing historical FaceGens, the time period on which pictures are updated, whether pictures are updated on demand all have no effect, the card always generated successfully.
So, I've tried just about every FaceGen option that I could toggle and the only way I can recreate that non-card issue is by being a non-commish in an online league.
If that's not the cause of your problem and you are on 11.2.18, you might want to provide your files to Andreas. Someone who has this problem will need to provide files at some point.