After Lumion 12.3.1 was released, some of you encountered issues with Layers and interface responsiveness that our developers have now fixed.

Important: To install this Hotfix, Lumion 12.3.1 is required and the patching process will not work with other versions of Lumion. The hotfix will be included in a later Lumion 12 standalone update.

1. Resolved issues:

• Mouse interactions with the user interface are more responsive and no longer sluggish in heavy Projects or Projects with low framerates.
• The Layer tab is more responsive when renaming Layers.
• The Layer name display has been improved.
• The name of Hidden Layers is now displayed when hovering over the Show/Hide icon.
• Layer names being displayed as numbers: this is now based on the available on-screen space instead of the number of Layers.
• Layer states no longer reset when loading a Project.

2. If you have not yet downloaded Lumion 12.3.1:

Please download and install Lumion 12.3.1 via your Lumion Account. 

• Knowledge Base: Lumion 12.3.1: Everything you need to know

3. If you already downloaded and installed Lumion 12.3.1:

3.1: Quit Lumion 12.3.1 if it is running.

3.2: Click on the download link below to download the hotfix:

• Download Link: Lumion 12.3.1_to_12.3.1.1_Commercial Hotfix.zip
• Download Link: Lumion 12.3.1_to_12.3.1.1_Student Hotfix.zip

3.3: Right-click on the Lumion 12.3.1 shortcut icon that you normally double-click on when you start Lumion 12.3.1.

3.4: Select Properties and click on the button Open File Location:

If you have installed Lumion 12.3.1 by overwriting the files in the Lumion 12.3 folder, please use the [Installation folder]\Lumion 12.3 directory instead.

3.5: Move the '.ZIP' file that you downloaded in step 1.2 to the Lumion 12.3.1 installation folder you opened in step 1.4.

3.6: Right-click on the '.ZIP' file and chose 'Extract Here' to unzip the contents of the '.ZIP' file in the Lumion 12.3.1 installation folder:

3.7: Confirm that you want to overwrite the existing files and folders by clicking on 'Yes to All'.

• Please choose 'overwrite' when Windows asks you if you want to overwrite the existing file.
• You need to have Administrative rights to write to this folder.
• If Windows does not ask you to confirm, you have moved the '.ZIP' file and/or unzipped it to the wrong location.
• In case you get an 'Access Denied' error message when extracting the files to the installation folder, please double-click the hotfix .ZIP file to open it and then drag the contents to the folder instead.

3.8: Start Lumion 12.3.1 again. The title bar should now display the new version number, i.e. 12.3.1.1.

4. See Also

• Knowledge Base: Lumion 12.3.1: Everything you need to know