I missed the plastic variant of OpenTech, OpenDirt and so on.
Contains all default OpenXXXRoad and OpenXXXPlatform blocks and some addons like straight platforms and slopes all with plastic (without black border) and penalty (custom sand, color #4,4,4) material/physics.
My test map (Summer 2020 - 09) with OpenPlastic items | including video
Update 2021-08-20: matching set
Instruction: unzip the downloaded file into your items folder (Trackmania\Items) and keep the folder structure or create an additional subdirectory named "iNDEX" and extract the ZIP-file here.
Download the following item into the subdirectory "iNDEX":