Toolbox Component Insert Error

[designer22]

Hi,
I created a custom component to add into the toolbox.
Everything looks OK,except I cannot add this to an Assembly.

When I configure Toolbox I can see everything in order.(toolbox-2. jpeg)
When it is inserted into Assembly, I am getting error message as shown in toolbox-1.jpeg

Can someone please help me solve this problem.
Thanks

 

[designer22]

Here is the other screen shot