Here you go (attached on this post).
Unzip in your Orbiter directory maintaining directory structure.
How to use:
1. Run the Scenario you want, pause and open the Scenario editor.
2. Press "New", select "Timer" from the drop-down menu and name it "timer" (or whatever you want, without the quotes).
3. Place the "timer" vessel wherever you want.
4. Exit the scenario.
5. Open the Orbiterroot\Script\timer.lua file with notepad
6. In the first line, enter the MJD you want the timer to countdown to
Example: launch_mjd = 55278.647452
7. (optional) Enter the name of the timer-vessel you created in the line right below the launch_mjd. If you named your vessel "timer" there is no need to change this line.
Example:
vessel name = timer -- leave the line as it is.
vessel name = display -- change it to: shiph = oapi.get_objhandle("display")
8. Save and exit.
9. Open the Orbiterroot\Scenarios\(Current state).scn file with notepad.
10. Enter the following: Script timer --Under the date, between the BEGIN_ENVIRONMENT, END_ENVIRONMENT lines.
Example:
BEGIN_ENVIRONMENT
System Sol
Date MJD 55278.5004612550
Script timer
Help CurrentState_img
END_ENVIRONMENT
11. Save and exit.
Done. When you run the (Current state) scenario you will have a working countdown display.
It can count from -100 to +100 hours to/since launch, defined by the launch_mjd line in the script.
Have fun, happy orbiting
--------------EDIT-----------------
Attachment removed. For the latest version, please download the file
attached on post #16 of this thread.
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