problem with changing application ICON

I have a problem:
> I have an application that is already in ROM Image of the phone with a stub, app_stub.sis is present in z:\system\install
> I want to upgrade the icons inside and the application icon as such so i do the following:
>> i have placed app_reg.rsc file inside c:\private\10003a3f\import\apps directory
>> have placed .mif and .rsc files in c:\resource\apps

> Now i try opening application it fails.. it doesnt launch my app.. ALL MY DLLS AND EXE ARE IN Z:\ and not available in C:\

Can any one help me on this!

regards,
DD