When a control have Anchor property set to Top, Bottom, Left, Right the designer did not preserve the original Size property value but assign to Size an higher value if you close and open the file.
This issue should be fixed. Let me know if you still have issues after updating to the latest release.
I have just tried to replicate your issue by adding a button to a window, setting the anchor to Top, Bottom, Left, and Right, but the size of the control did not change after setting these, closing the designer, and reopening it.
What version of WiseJ are you running?
Would you mind uploading a sample of your issue?
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