Publisher Warner Bros. Interactive Entertainment and developer Rocksteady have released a patch for the PC version of Batman: Arkham Knight which fixes a bug that disabled the game's rain effects and other issues, the companies have announced.

Warner Bros. Community Admin Yorick said that the patch is being released now, and that the companies will continue to release interim patches while it continues to work on improving performance issues the game suffered from since it launched on PC last week.

Updates in the first patch include:

• Fixed a crash that was happening for some users when exiting the game
• Fixed a bug which disabled rain effects and ambient occlusion. We are actively looking into fixing other bugs to improve this further
• Corrected an issue that was causing Steam to re-download the game when verifying the integrity of the game cache through the Steam client
• Fixed a bug that caused the game to crash when turning off Motion Blur in BmSystemSettings.ini. A future patch will enable this in the graphics settings menu

"Rocksteady is leading our team of developers and partners as we work on the PC performance issues that players have been encountering," Warner Bros. said. "The work is significant and while we are making good progress on improving performance, it will take some time to ensure that we get the right fixes in place "

These are the issues that Warner Bros. said it's dedicating its resournces to in order to improve the game:

• Support for frame rates above 30FPS in the graphics settings menu
• Fix for low resolution texture bug
• Improve overall performance and framerate hitches
• Add more options to the graphics settings menu
• Improvements to hard drive streaming and hitches
• Address full screen rendering bug on gaming laptop
• Improvements to system memory and VRAM usage
• NVIDIA SLI bug fixes
• Enabling AMD Crossfire
• NVIDIA and AMD updated drivers

Warner Bros. suspended sales of the PC version of the game last week until these issues are fixed. Graphics card giant Nvidia has said it is offering its QA and technical assistance to help quell the problem.

Posting on Twitter, studio co-founder and director of the Batman: Arkham series, Sefton Hill, also said the studio has its "best engineers" helping to fix the issues.