jensj12

There is currently an issue with objects disappearing after save/load (they're no longer invented). Enabling the ignore research cheat should get it to work again. See #21496.

You can always open a park with expansion objects even if you don't own them and they will function properly (the simulation will run exactly the same). The only difference is that you won't be able to see the expansion objects.

Assuming you do have access to a working disc drive on your Linux machine and already got OpenRCT2 to work with vanilla RCT2. I'm not sure how the file structure on the CD is. If it's just plain data files, move them to the corresponding folder in your RCT2 (not OpenRCT2) folder on your machine. If it's an installer, you will first need to extract the files from it. You might be able to unzip it by changing the extension, but otherwise I don't know.

It seems that queue line TVs and entertainers can help increase this time.

Can't post a challenge without completing it yourself. MiniChallange.park

You need RCT2 to run OpenRCT2. RCT Deluxe is RCT1, which can be linked to OpenRCT2 to unlock some extra features, but it's not enough in itself to run the game.

Make sure you have the relevant expansion (Time Twister) enabled in the dropdown in the top-right. It might be set to vanilla RCT2 only.

For quick yet difficult challenges, I usually setting unusually tight constraints on the number of tiles used. For example:

The title sequence editor is now a plugin (and thus no longer ships with OpenRCT2 by default): https://openrct2plugins.org/plugin/MDEwOlJlcG9zaXRvcnkzMzI1MDA3OTY=/title-sequence-editor

The problem with most track pieces is the artwork required for it. A chainlift isn't just added to a track piece, it's a whole new track piece with its own artwork. The zero-g rolls that currently exist were added by someone who put in a lot of work to get the graphics right, which is a very tedious task. New track pieces will be added to coasters when there is a sufficient audience for it and someone does the artwork (it has to match the existing artwork as well, which I think is the biggest issue). Getting currently non-existing pieces to work (such as beyond vertical drops) is the 'easy' part. So the idea is there, it's just a ton of work and therefore takes time (for an open source project, that means years).

This seems like a feature that would be suited for a plugin. I'm not expert on plugins though, so I have no idea whether such a plugin already exists or that you'd have to write it yourself (and whether that's possible with the current plugin API, but this seems simple enough).

Someone who works on pathfinding. OpenRCT2 is a free open source game, so if you really want something to be changed, gotta do it yourself (but bear in mind that changes to the game's balance need to be approved, preferably before working on it). Or hope anyone else kindly takes it upon them... Just know that issues with larger parks than originally possible are known and will likely eventually be fixed, but with people only working on it in their free time and many other issues still needing improvement, it might take some years. The other option was to not raise the game limits for a few more years.

OpenRCT2 requires a copy of RCT2 or RCT Classic to work. Their only difference is that Classic comes with recreations of the RCT1 (Deluxe) scenarios. You don't need RCT World for anything in OpenRCT2. Regardless of whether you use RCT2 or RCTC, also adding RCT1 unlocks some extra wall textures and adds the original RCT1 scenarios. The best possible combination would be RollerCoaster Tycoon®: Deluxe and RollerCoaster Tycoon® 2: Triple Thrill Pack (the latter can be exchanged with RCT Classic, but that is usually more expensive).

OpenRCT2 no longer uses the .sc6/.sv6 file format (though it can still load them). All new saves/scenarios made with OpenRCT2 will be in .park format.

g2.dat is supplied by openrct2. A size mismatch usually indicates a mixed install, which means you have files from different versions of openrct2. Re-installing usually does the trick.