Hi All,
I'm just trying to help here. So let me get the senerio correct. You have signature 1 and signature 2 installed in computer A. In computer B, you also have signature 1 and signature 2 installed as well. Is this correct?
Before assuming that this is an iCloud syncing problem which I hope not, please check this:
1. Assuming that you have already installed signature 1 and signature 2 and it is working fine on computer 1, make sure you have signature 1 selected in the "Choose signature" drop-down menu (located at the bottom) in Mail>Preferences>Signatures for your corresponding Mail account. The same goes for signature 2. After this is done, when you open a new compose message window, your html signature will pop up near the bottom of your window.
2. When installing your html signature into Mail, you have to ensure that the .mailsignature file is locked after you edit it with your html codes. For more details on this, please view my tutorial: http://mydesignpad.com/create-a-html-email-signature-for-mac-os-x-mountain-lion- 10-8/
Hope this helps, let me know how it goes.