We are going off topic, before some moderators delete these posts I suggest you open a new discussion where we can talk about these things and where these posts will be moved.
Dview is not a program for editing images, it is a program to convert them.
You cannot open images in the NNG Bitmap format with any editing program, you need to convert them to png or normal bmp format to be able to modify them.
After making the various changes, they must be converted back into the NNG Bitmap format to be used by iGO.
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