Compatibility of Bloodmoon and Tribunal

[Apple Strudel]

I have the original (non GOTY) edition of Morrowind on disc and as far as I can see openmw and tes3mp both require bloodmoon and tribunal.

Where can I get these? Will the steam copies be compatible? (I.e. can I just install them to my morrowind folder)

Additionally after changing to openmw can I still use the elder scrolls construction set or does it become incompatible?

I'm curious because I would like to try and run some tes3mp and see if I can get some friends to play

[testman]

OpenMW and TES3MP don't necessarily *require* Tribunal and Bloodmoon. However in case of TES3MP you will see that you do need them enabled in order to join most servers.

And yes, both OpenMW and TES3MP work well with game data from Steam.

You can still use Construction Set, as OpenMW / TES3MP just take game data, they do not make any changes to it and neither do they interfere with original game executable.
Keep in mind that TES3MP servers check for "hash" of each game data file in order to verify that player is connecting with same game data as everyone else, and changing the game data with CS will change the hash.

[Apple Strudel]

So if I download the DLC from steam it will work fine qith my disc copy of morrowind?

And with construction set mods, I just have to disable them when I go to join a server, and that works as normal?

[testman]

From what I see, Steam does not differentiate between the main game and expansions.
Morrowind GOTY on Steam is a full package, meaning that if you buy it, you get main game and expansions in a single download.
While you could try to combine expansion data from Steam with game data from CD, I don't see why this would be necessary, as you would already have all required game data in one place.

And yes, OpenMW launcher (that comes with TES3MP) allows you to easily configure which mods to use. It even allows for "presets", meaning that you can change from one combination of mods to another with a simple selection on a drop-down menu instead of going through the whole list of mods each time.
Which mods / content you need to have enabled depends on the server you are joining. In most cases you will need to have Morrowind, Tribunal and Bloodmoon enabled. But if you are joining some server that requires additional mods / content, you need to make sure that you have the right version of that content installed and enabled in order for server to accept your connection.