When I can't get mods to work, I usually move my mods folder to my desktop and copy them in one by one or in a small batch, say 5 of them, to see which one is causing issues. Deleting cache file before testing each batch of mods.
For reference the game cache files are:
CasPartCache.package ; compositorCache.package ; scriptCache.package ; simCompositorCache.package ; socialCache.package
Load the game.. If you don't see the opening intro. That means the skip the intro mod is at least working. Quit without saving.
If you find mods not working when trying a batch of 5, try a smaller batch of say 3 mods per batch, but don't forget to delete cache each batch test. This help clear the game's memory of the mods that aren't working.
If you want to know more about fixing issues with mods, we have a post on that linked below:
Sims 3 - How-To: Fix Problems with Mods/CC
https://www.carls-sims-4-guide.com/forum/index.php?topic=31759.msg506010#msg506010