Yassin,

>1. I have created a new class and inherited from mmPickListForm and then when I try to view the form in design mode I get
>
> Object reference not set to an instance of an object.
> Hide
> at OakLeaf.MM.Main.Windows.Forms.mmPickListForm..ctor(mmPickListParameters pickListParms)
>at OakLeaf.MM.Main.Windows.Forms.mmPickListForm..ctor()
>
>
>2. I am inheriting because I want to change the background color of the form, what do I need to do to call my mmpicklistForm when a user clicks on mmpicker control.

I just tried to create a subclass and it worked fine. Did you add any code to the constructor of the subclass? If so, this may be the culprit. Check out the constructor of the source code in mmPickListForm and notice it is bracketed in a check for mmAppBase.IsRunning. You need to do this for your code too.

Best Regards,