Thank you very much Eric for good and right tip.
Yes. When I call SW portal using .dll as above, or I used the shortcut above it works! Bingo!
Well, I have displayed the SW portal shortcuts by allowing Software Portal Plug-in Policy and use it for now.
Note: In Altiris 71 it works also when I use http://<servername>/Altiris/SoftwarePortal/UserPortal/home.aspx I can request the software (open the dialog)
So when I use the SW portal shortcut I can request software and dialog is opened succesfully
BUT it is not my victory!!!
Next issue is comming. When I request the Pre-Approved software it goes only to status Open but not to wanted Approved. So not quick delivery task is generated. Neither I am not able to change this status in Administration portal. (But it shouldn't be needed)
Here is my publishing of the SW resource.
When I request the same software again, it return naturally following error.