Hi,
What is the explanation of the next issue:
I have ordinary skin with 2 panes: content pane and side pane.
I place some custom module i developed in the content pane.
In the side pane there are some other dnn modules.
My module has few controls which are loaded dynamically by calling
the same tab id with the control name and optional parameters.
Whenever the module first page is loading everything appears fine include
the side pane with its own modules.
But when some control is being called - the side pane hasn't any modules...
My module appears fine on the content pane but all the modules which were
placed in the side pane disappear.
I noticed this is true for every module in dnn which calls another control - only the
content pane is being shown...
Why? Is there any option to always present modules in the side pane?

Thanks.

its the design of DNN to only show the one module when the CTL and MID parameters are used.  If you want your control to show along with other controls, but change sub controls, you will have to make your own custom handling.

The issue may come up that if you have two or more instances of your control on the same page, then how is it handled.  This is the reason behind the behaviour of the CTL and MID parameters, I'm fairly sure.