Help with input device

I'm trying to read a USB device that allows me to test rotary encoders. The device enumerates as a standard HID controller although not as joystick or mouse etc... I have a .dll from the manufacturer and have placed it in the userlibs dir. I have also created a .decls file which looks like this:

.lib "spinkit.dll"

SpinKitOpenDevice%():"SpinKitOpenDevice"
SpinKitCloseDevice% (devHandle%):"SpinKitCloseDevice"
SpinKitRead%(devHandle%,SpinData*):"SpinKitRead"
SpinKitReadImmediate%(devHandle%,SpinData*):"SpinKitReadImmediate"
SpinKitGetNumDevs%():"SpinKitGetNumDevs"
SpinKitGetDeviceHandle%(numDevice%):"SpinKitGetDeviceHandle"
SpinKitGetProductId%(devHandle%):"SpinKitGetProductId"
SpinKitGetRevision%(devHandle%):"SpinKitGetRevision"
SpinKitGetThreadHandle%(devHandle%):"SpinKitGetThreadHandle"
SpinKitGetSerialNumber%(devHandle%):"SpinKitGetSerialNumber"
SpinKitSetTimeout(devHandle%,timeout%):"SpinKitSetTimeout"
SpinKitVersion%():"SpinKitVersion"

All of the functions seem to work fine except I cant seem to figure out how to use SpinKitRead%(devHandle%,SpinData*) and SpinKitReadImmediate%(devHandle%,SpinData*).

I'm sort of familliar with using a bank to point the data to as in GetCursorPos from user32.dll but it doesn't seem to work the same way.

In the documentation for the device they give a data structure that looks like this:

typedef struct _SPINKIT_DATA
{
SPINKIT_HANDLE Device;
int Spins[6]
BOOL Buttons[7]
}
SPINKIT_DATA, *PSPINKIT_DATA;

I was also provided with a working example app with source code which runs fine but it is written in Delphi and I am not familliar with the syntax.

It should be fairly straight foreward retrieve the data in Blitz and the SpinKitGetDeviceHandle%(numDevice%) function works fine but SpinKitRead%(devHandle%,SpinData*) returns zero when it should be nonzero and there is no data in the bank.

Any help would be greatly appreciated.

Thanks!