>>67567441From my experience after finishing KD;
When reading new jukugo it's still tough to recall the mnemonics, but I write them a few times and add them to a vocab deck. Once I have an actual jukugo for a kanji memorized the next encounter I can recall the reading and his mnemonic almost immediately.
It helps that it's enforcing the reading of 2, 3 or more kanji with a single word, so it only gets easier and easier.
Also, having a memory of where you learnt your vocabulary from helps much more that learning from a lists of words you culled from someone else, imo.
Just keep reading and be patient I guess.