I don't have SimBrief installed and since the last Coualt 2.5.0 update, I have Reload SimBrief in red in the GSX menu ?.Before this update everything was working fine.
It's now working fine, it wasn't before.
Before the update, you had to manually click the button to load Simbrief and, before you did that, the button was in an undefined state ( neither red or green, it was grey ), now as soon you open the GSX menu, the Simbrief status will be check automatically, on the background, without delaying the menu opening until the Simbrief status could be checked.
The SimBrief button is not just red: it shows a small text beneath the button, with a reason why it's red. If you don't see it, it's possible you might have to resize the GSX menu with the mouse to make it taller, so you'll see the text below the button.
And of course, if you click it, it will show whatever error/problem it has, on the top of the screen.