Today, we are bringing a core update for Train Simulator 2021 that includes optimisation and loading performance improvements aimed at addressing long load times experienced by players when loading content that is contained within asset package files (.ap). This update has been tested vigorously but, given the vast scale of the Add-on catalogue, User Generated Content (UGC) and the Third-Party Add-on catalogue (non-Steam), it is entirely impossible to test every possible combination. We are, therefore, making these improvements available as an "opt-in" update. This means, to utilise the benefits of this update, you will need to do some additional steps as explained below. To use this update, please follow the steps below: Open Steam and navigate to your Steam Games Library. Locate and right-click on Train Simulator. Select Properties from the context menu to view Train Simulator's Properties Dialog. In the General Tab, scroll down until you see Launch Options. Click in the text entry box and type (see image below): -fastload Close Train Simulator's Properties Dialog to save your changes. The next time you click Play, Train Simulator will use the new code and you should see significant improvements to loading times for many add-ons, mostly for those you've purchased from Steam. Should you run into any problems when loading an add-on whilst opted into the update, you will need to carry out additional steps before contacting Customer Support, as explained below: You should first opt out of the update by repeating the above steps but deleting the text from the Launch Options in Step 5. Re-load Train Simulator and attempt to repeat the steps that produced the problem. If the repeated test DOES NOT result in the same problem once you are opted out of the update, you need to let us know by contacting Customer Support and advising you are opted in to the performance update and which add-on you experienced the problem with. Customer Support will guide you on what details to provide which will help us in tracing the cause. Please note: If you use a desktop shortcut to launch Train Simulator, you will need to also add the above launch option to the shortcut. Launch options only work when clicking Play in Steam and, if they are not also added to your shortcut, you will not see any difference. To add the launch option to your desktop shortcut, follow the steps below: Right-click on your desktop shortcut and select Properties. In the properties dialog, click the Shortcut tab. Locate and click in the Target text box. Scroll to the end of the text, add a space then type: -fastload Click Apply, then OK to save the changes. When you next launch Train Simulator from the shortcut, you will see the difference in loading performance. The update will download automatically when it becomes available. Players should allow at least 24 hours after restarting Steam for the update to appear and before contacting Customer Support. The approximate download size is ~16 MB.