Kerbal Space Program

Description:
The DLC will not load properly if the file path contains spaces and plus signs. Plus signs with no spaces works. Spaces with no plus signs works. Just can't put both into the file path. These combinations worked up to version 1.7.3.
The program gives the following error at the main menu screen:

Expansion Loading Failed
The following expansions failed to load:
D:\KSP Installs\1.8.1+MH+BG\GameData\SquadExpansion\MakingHistory\makinghistory.kspexpansion: Unable to load the Expansion Master Bundle.
D:\KSP Installs\1.8.1+MH+BG\GameData\SquadExpansion\Serenity\serenity.kspexpansion: Unable to load the Expansion Master Bundle.

The parts from the DLCs are viewed to be loading as the parts list scrolls by during the loading phase. The DLC and their version numbers are not on the main menu screen. Mission builder is unavailable. The DLC parts are available in the VAB and spaceplane hanger but the DLC specific functions do not work.

To Replicate:
Install KSP and DLC into a file path similar to first example below and launch KSP normally.
For example:
D:\KSP Installs\1.8.1+MH+BG\ ( This path causes error condition. Contains spaces and pluses. This format worked previously in 1.7.3. )
D:\KSP+Installs\1.8.1+MH+BG\ ( This path works. No spaces. Only pluses. )
D:\KSP Installs\1.8.1 MH BG\ ( This path works. No pluses. Only spaces. )

System specs of systems used for testing:
i7-6700K, 32GB ram, Geforce GTX 1080, Windows 10 1903 64 bit (US Eng localization)
and
HP notebook i5-8250U, 32GB ram, Radeon R7 M340, Windows 10 1903 64 bit (Us Eng localization)

This affects KSP 1.8.0 and 1.8.1 versions from the KSP store and Steam if the Steam library folder contains a plus sign.
The base game works fine regardless of the file path.