Fallout: New Vegas creator Obsidian Entertainment has explained why the sprawling openworld RPG suffers from technical issues  including console-crashing bugs and corrupted save files.

The Bethesda Softworks published game was built with the creaking Gamebryo engine  used to construct The Elder Scrolls IV: Oblivion and Fallout 3 before Fallout: New Vegas.

But Gamebryo wasn't Obsidian's tech - a fact that contributed to New Vegas' well-documented problems, Obsidian said.

The Square Enix published action RPG Dungeon Siege III, however, is the first game to be built using Obsidian's own, internally created game engine, Onyx.

For project director Rich Taylor, it's made all the difference.

"Stability and being bug free are extremely high priorities on this project, and we actually talk about it internally constantly," he explained to Eurogamer in a new interview. "The advantage here we have over, for example Fallout, is when we have a question about how something works, I walk 10 feet outside my office door and go talk to the programmer who wrote it. That's a lot different than trying to get someone on a mailing list, or get someone on the phone who's in a different time zone or across the country. Those sort of things have made it possible for us to stabilise things and keep things working as well as we like.

"Here we have the advantage of, no matter who runs into a crash issue, we're able to get it up on the screen with a stack dump and look at it and peel back the information on it, and identify exactly what happened and get it fixed. That's been a change.

"When we've worked with other engines sometimes you get a crash and you're like, well, I don't know. We didn't write this. Why is this happening? You get a bunch of engineers in there trying to reproduce something that takes hours to reproduce. Those kind of things can be difficult when you're not able to develop your own tech. But our crash and stability tools on this project have been phenomenal.

"So having our own technology, having the actual engineers who wrote it right here, available and working on it, and they're very passionate about making it as stable and solid as possible, certainly worked well for this project."

Since New Vegas' hugely successful launch, Bethesda has released a number of patches designed to improve the performance of the game.

In October last year Bethesda told Xbox 360 owners to save often while playing as it worked to fix a bug that prevented gamers from loading save files.

"Well, no one wants to run into a crash," Taylor replied when asked whether gamers complain too much about bugs and glitches. "We're gamers, too. I certainly go home and like to play other games that are out there. And when you run into a crash and it disrupts your experience, that's not fun for anyone. We understand that.

"That's why, as the project director on this game, I'm very militant about us addressing the crashes and memory issues."