windows form doesn't display any item.

Ive created supersimple form. just drag and drop several labels and image.
 i call it from my program onclick:
progressform frm = new progressform();
frm.open();
---somesting here---
frm.close();


my form shows as expected, but without labels. there are white rectangulars instead of each all items(tried with label, checkbox, image)
it seems that form cannot load this items, although it can load by itself. 
I didn't do anything with default code in form.
What's wrong? 
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