Time Trial Misty/Foggy bugs (trying to fix via Hexedit)

Metropolis Street Racer has a known bug in Time Trial mode where ghosts saved under 'misty' or 'foggy' weather revert the VMU file (MSRCHALL) to clear weather when you try to replay it.  The ghost itself will also be missing even though the file states it's present.

My workaround is as follows:

1. Create a empty Time Trial file (MSRCHALL) on your required course with either misty or foggy weather.
  
2. Select the Time Trial file in question to play but once you get to the screen where the weather is displayed (final screen before the race), back out all the way to the main menu screen using the B button.  

3. Go into Time Attack from the main menu, choose Time Attack again on the next menu (not Ghost Attack) and select the exact same course.  The weather should come as misty or foggy on the info screen just before the race.

4. Set a ghost, then exit and save.  

When you replay the same ghost (MSRGHOST) via Ghost Attack, the weather will be misty or foggy accordingly.

Unfortunately the drawback of this workaround is that you can only have one ghost for each course per VMU unlike Time Trials where you can save multiple ghosts for the same course if desired. This is because the MSRGHOST file's '3-number extension' corresponds to a particular course.

I attempted to fix the problem by using the Hexeditor in Dream Explorer.  I created an empty Time Trial and figured out that address 0x00308 controls the weather (00-07, 00 being clear, 01-05 are wet conditions, and 06 and 07 are misty and foggy respectively).  I then took a Time Trial ghost that reverted back to clear weather (and missing ghost) and adjusted the hex address 0x00308 to 07 in order to activate foggy weather.  

However while the weather was indeed foggy again on my replay, the saved ghost car was still nowhere to be seen.  I then hex adjusted the whole of line 0300 to '00' with the exception of the 0312 and 0313 numbers that were left alone.  On replay, the saved ghost reappeared but naturally the weather was clear.

I then took a look at the MSRGHOST file created via my workaround and noticed its line 00308 did not have a value at address 0x00308 but did have one at at 0x00304 and sometimes 0x00300.  I hexedited the Time Trial's 00300 line with the exact same values found in the MSRGHOST file equivalent.  However on replay, the weather was again clear and no ghost was present.  The Time Trial programming seems to expect a value at 0x00308

After playing around with hex values for quite a while, I decided to delete my original MSRGHOST file and rename my MSRCHALL file to MSRGHOST with the relevant course extension.  Before doing this I reverted the hex values on line 0300 back to their original values.  Low and behold, when replaying said file via Ghost Attack the weather was foggy and the ghost was present.  It seems that MSRGHOST and MSRCHALL (Ghost saved inside) files are exactly the same minus the names.  

Unfortunately I think this means the fault lies within the Time Trial programming itself and therefore it is impossible to replay ghosts with foggy/misty weather via that option, regardless of how much you mess around with the VMU save file.