In my case I'm trying to use coinb.in to create and use a 2-of-2 address, but I'm stuck. I've done all the operations below from coinb.in:

1 ) generated 2 sets of Bitcoin keys (so 2 addresses, 2 public uncompressed keys, and 2 private keys)
2 ) generated a 2-of-2 p2sh address using the public keys from step #1
3 ) sent 0.0022 BTC to that p2sh address

So far so good. The funds are in the p2sh address, with 12 confirmations as I type this.

This is where the problems begin.

When creating a transaction, it looks like it doesn't support sending to p2sh addresses  , so I can't send change back to the address that I just created, nor to any other p2sh address (I have tried a couple of them). It only generates the transaction hex when I use non p2sh addresses. That is a significant issue for me. I really need to send the change back to the same address.

Anyway, I decided to retrieve the BTC back to one of my non p2sh addresses, and I'm still stuck. Here's the steps I've taken:

4 ) generate new transaction using redeem script from step #2, sending 0.0021 to a normal bitcoin address and with 0.0001 fee. Transaction hex is generated successfully.
5 ) verify the transaction hex from step #4. the verification is successful, and the input and outputs look OK.
6 ) sign transaction hex from step #4 with first private key from step #1
7 ) sign transaction hex from step #6 with second private key from step #1
8 ) broadcast the transaction hex from step 7
"TX rejected"

I noticed that the signed transaction hex from steps #6 and #7 cannot be verified like the original transaction hex in step #5, with "Unable to decode" error. However when pasting those same hex strings to https://coinb.in/decode-raw-transaction.html it decodes them successfully.

Any idea what could be going wrong with this?