Payment plugin installation

Hello,

I need to create a couple of custom payment plugins. I've looked through the documentation and have created a fairly basic plugin. It installs through Joomla's extension installer like I'd expect, but the problem is that when I select it in HikaShop (via system > payment methods > new), it goes to a page without content. (see attachment--It doesn't give an error, and it doesn't go to a blank page; it just doesn't have the plugin's options).

Is this typically a symptom of something I've done wrong in the plugin, or a system configuration?

Thank you!

-- url of the page with the problem -- : administrator/index.php?option=com_hikashop&ctrl=plugins&task=edit&name=accttransfer&plugin_type=payment&subtask=edit (It's a non-public site, and I can't give out the root domain. Sorry.)
-- HikaShop version -- : Starter 2.2.1
-- Joomla version -- : 3.1.5
-- PHP version -- : 5.3.2
-- Browser(s) name and version -- : Chrome 29.0.1547.76 m
-- Error-message(debug-mod must be tuned on) -- : none given

I have gotten *one* of my plugins to work; I'll keep digging. Thank you!