Hello,

When I started Q3, I selected a White background in the initial dialog window. I opened a copy of a good Q2 file and saw that ALL entities with Q2 Black/White color where forced to be White. Andrew explains this as a mean to avoid unreadable items against the background colors. Remember I selected White as background ? I guess Black/White entities could be better kept as Black ?

Following Andrew's advice, in Application Preferences ==> Graphics View, I unchecked the Auto correct black and white colors check box. The background settings is white. OK.

I went through a process of changing the White color for several layers to Black. I also had to change the color codes for the hatch areas. For instance, the hatch area layer "055_F_Murs" has "14-76-255 / 255-197-179" values in Q2. Why these values are auto corrected to "30-128-255 / 255-191-127" ?

After these changes, I saved the file, closed Q3 and opened the file again.

Catastrophique ! All "Black/White" layers were back to Black and the hatch colors were back to the "auto corrected" values.

Changing the background color to black then white seemed to solve the problem : the layers kept the Black color. Actually it was just an illusion.

Yesterday too much confident, I spent the whole day, modifying layers to Black, adding new layers also Black or custom color, checking the line weight (replacing the "default" (?) value of 0.25 mm with my preferred default value of 0,00 mm, I've posted on the forum about this) and so on. I saved the file, closed it.
To-day, nearly all layers have lost their colors :
- Black ones are again White,
- custom color are "auto corrected" as above for "055_F_Murs",
- only the standard non Black/White colors are preserved, like Blue, Magenta etc.

At this point, I can't continue using QCAD 3 with enough reliability as my color settings are __always __lost. This is why I qualify this bug as CRITICAL.
I don't want to use a Black background or a Light Blue one. Why do you think all old "green on black VDU" were replaced with "black/color on white" displays, to begin by Apple ?

NB I already reported this but can't find it in the list (maybe because I forgot to enter a summary ? No warning, happily I had a copy with Notepad), sorry for the duplicate.