How to: Save Tif as Gif with transparent background in VB.Net

Hi,

I am trying to save a tif file to gif and at the same time setting the white background transparent. I did this in Corel Photo Paint 11 with the following code:

Call PhotoPaint11App.CorelScript.FilterGIF(0, 0, 1, 1, 0, 0, 0, 0)
Call PhotoPaint11App.CorelScript.FileSave(gWebFolderMain & gMVID & "-NakkeO.gif", PHOTOPAINT.cdrFilter.cdrGIF, 0)

Now in Corel Photo Paint X5 this doesn't work any more. What have changed and what am I doing wrong. According to documentation it seems to be correct.

Please, any help would be appreciated.

Best regards
Pål Eilertsen