Never used Abacus but I have the same problem with AB. I've seen deposits go as high go 50-100 confirmations before being deposited. The incoming deposit notification doesn't work for me on AB either, it always says no incoming deposits detected then all of the sudden 62 confirmations later or whatever it's there. I've used AB a good bit, ASAP a 4-5 times and BoHo is quickly becoming my favorite market soon surpassing the number of orders I've done on AB.
I made a deposit to Bohemia last nigth, over $500, and they credited it to me with less than 10 confirmations. 10 confirmations is supposed to be the minimum for XMR (i'm assuming that's what we're talking about because who uses BTC anymore) but they still gave me the credit and let me place my order. They also encourage opening support tickets for long deposit or withdrawals. I had a withdrawal get stuck sitting 24 hours and opened a ticket and they responded and had me whole in less than an hour. Totally not shilling, I've been using markets for 9 years now and thats some of the best support I've seen.
All deposits are credited automatically now.
Big update is about to come, please stay tuned.