andyp,
31a 4-word definition; abbreviation for "cases" with a "rule" around it, all reversed
34a obsolete definition (x "before"), ; abbreviation and last letter ("finally"), all reversed
5d first letter, then abbreviation for "in English"
21d anagram ("runs out") of all of: second word + final letter ("in the end") + abbreviation for "money"
6a I can't parse either - any help?
And 36a I get an extra word ("fell") that doesn't seem like it should be, so struggling there too.
A fantastic puzzle, though. I obliterated the letters with large dark 'symbols' and coloured the background appropriately, though I guess that there are different interpretations. Thanks Ifor!