you refer to the 'Text Editor' GUI component template. In fact, this component is implemented to use internally the 0xA0 sign instead of the blank 0x20. It is a kind of trick to simplify the implementation. The Text-View used by the component to display the entered text is optimized to automatically eliminate blank signs. Therefore, we replace blanks by the 0xA0 sign, which is not eliminated.
If your font does not contain any glyph for the sign 0xA0, you can configure the font resource to use another glyph instead. For this purpose you have to modify the attribute Ranges of the affected font ressource to map the code 0xA0 to e.g. 0x20. Assuming, the attribute was originally configured with the range 0x20-0xFF, then change it to the following expression: 0x20-0xBF,0x20:0xA0,0xA1-0xFF. For example:
Does it solve the problem?