DynaWrap worked for a simple case
Here is a rough summary of a test:
0. Download dynawrapNT.zip
and extract the dynawrap.dll file (MD5: ca218f1aa4bf60d5deacebe0f55a2f95).
1. As admin, run cmd.exe and in the directory containing dynawrap.dll execute:
2. In a .js file of some Qatapult plugin, appropriately add something like:
dw = new ActiveXObject("DynamicWrapper");
dw.Register("User32.dll", "MessageBoxA", "f=s", "i=hssu", "r=l");
dw.MessageBoxA(null, "Here is a test", "So?", 0);
3. Execute plugin functionality that calls the code added above.
4. Observe a message box.
Tested with Windows 7 Pro 64-bit and Windows XP Pro SP3.
The following was helpful: How to use DynamicWrapper?
Attached the dynawrap zip file for the time being.