I've suggested ways of doing this, but it just gets bumped off and falls on seemingly deaf ears, so I'm submitting it in the problem in the hope you'll come up with a better solution.
I've just counted up and it takes me a minimum 6 clicks to attach a receipt to a transaction. This is in addition to the clicks finding the transaction in MoneyWiz and the receipt in Finder.
This may not seem like a lot of clicks, but if you only file them once or twice a month and have 100 or so receipts, the RSI issues invoked from this process get old pretty quick.
Please think of a better way of doing this, the best way I can think is to enable dragging and dropping onto the transaction itself, rather than having to click on Options and Edit.
Please go to MoneyWiz's for Mac Preferences -> Transaction layout and move the "Attach receipts" field to the Basic fields so that it's always visible.
When adding an attachment, double click on the transaction you want to edit then drag and drop your attachment there. This should significantly reduce the number of clicks needed.
We are investigating other options of improving this but we're also working on other features at the same time that we've been promising for a long time and that are requested by many users.