The spaces in my drawing as well as any new spaces I want to place appear too dark and I want to lighten the colors.
To change the colors of existing and future spaces, do the following:
1. Open Dataset Explorer.
2. Select the Space Part and find the type of space you want to modify and set it the way you want and click the Commit Changes button.
The spaces that already exist in your drawing will not reflect the symbology change until you Apply Active Part.
3. Go to the Building Designer Pull-down - Family and Parts - Verify Part and Family and in the dialog, select the (multiple) Spaces you want to update and click the Apply Active Part button.
4. The selected parts will highlight in your drawing. Accept the selected parts in your drawing and the symbology should update in your view.
Any new spaces placed should reflect the new color/symbology.