Just FYI for 1.17 compatability: Tried mod in 1.17.2 and the game crashed when trying to draw with a black crayon:
Game Version: v1.17.2 (Stable)
9/3/2022 05:08:56 PM: Critical error occurred
Loaded Mods: animalcages@2.0.6, cavepaintings@1.3.1, necessaries@1.1.2, betterruins@0.0.1, cralutweaks@1.0.2, hideandfabric@1.2.5, HoneyPress@1.1.1, hudrealtimeclock@1.0.0, meteoricexpansion@1.2.1, leadroof@1.2.0, OresAPlenty@3.0.0, primitivesurvival@3.0.5, qptech@1.10.4, rlmoonsun@0.1.1, rustandrails@1.0.3, game@1.17.2, SimpleMobFootSteps@1.0.3, carrycapacity@0.6.5, fromgoldencombs@1.3.14-pre.1, petai@1.5.3, prospectorinfo@3.2.0, creative@1.17.2, redirectlogs@1.0.0, survival@1.17.2, xrowboat@0.0.4, cats@1.5.1, tradercamps@1.0.2, glassmaking@1.3.3, stonepiles@1.0.6, wolftaming@1.5.2
System.MissingFieldException: Field not found: 'Vintagestory.API.Common.Block.SideSolid'.
at cavepaintings.src.PigmentItem.OnHeldInteractStart(ItemSlot slot, EntityAgent byEntity, BlockSelection blockSel, EntitySelection entitySel, Boolean firstEvent, EnumHandHandling& handling)
at Vintagestory.Client.NoObf.SystemMouseInWorldInteractions.TryBeginUseActiveSlotItem(BlockSelection blockSel, EntitySelection entitySel, EnumHandInteract useType, EnumHandHandling& handling) in VintagestoryLib\Client\Systems\Player\MouseInWorldInteractions.cs:line 860
at Vintagestory.Client.NoObf.SystemMouseInWorldInteractions.TryBeginUseActiveSlotItem(BlockSelection blockSel, EntitySelection entitySel) in VintagestoryLib\Client\Systems\Player\MouseInWorldInteractions.cs:line 835
at Vintagestory.Client.NoObf.SystemMouseInWorldInteractions.HandleMouseInteractionsBlockSelected(Single dt) in VintagestoryLib\Client\Systems\Player\MouseInWorldInteractions.cs:line 540
at Vintagestory.Client.NoObf.SystemMouseInWorldInteractions.OnFinalizeFrame(Single dt) in VintagestoryLib\Client\Systems\Player\MouseInWorldInteractions.cs:line 89
at Vintagestory.Client.NoObf.ClientEventManager.TriggerRenderStage(EnumRenderStage stage, Single dt) in VintagestoryLib\Client\Util\ClientEventManager.cs:line 199
at Vintagestory.Client.NoObf.ClientMain.TriggerRenderStage(EnumRenderStage stage, Single dt) in VintagestoryLib\Client\ClientMain.cs:line 1176
at Vintagestory.Client.NoObf.ClientMain.RenderToDefaultFramebuffer(Single dt) in VintagestoryLib\Client\ClientMain.cs:line 1364
at Vintagestory.Client.GuiScreenRunningGame.RenderToDefaultFramebuffer(Single dt) in VintagestoryLib\Client\MainMenu\Screens\GuiScreenRunningGame.cs:line 204
at Vintagestory.Client.ScreenManager.Render(Single dt) in VintagestoryLib\Client\ScreenManager.cs:line 711
at Vintagestory.Client.ScreenManager.OnNewFrame(Single dt) in VintagestoryLib\Client\ScreenManager.cs:line 615
at Vintagestory.Client.NoObf.ClientPlatformWindows.window_RenderFrame(Object sender, FrameEventArgs e) in VintagestoryLib\Client\ClientPlatform\GameWindow.cs:line 132
at System.EventHandler`1.Invoke(Object sender, TEventArgs e)
at OpenTK.GameWindow.RaiseRenderFrame(Double elapsed, Double& timestamp) in C:\Users\Nexrem\Desktop\transfer\opentk\src\OpenTK\GameWindow.cs:line 479
at OpenTK.GameWindow.DispatchRenderFrame() in C:\Users\Nexrem\Desktop\transfer\opentk\src\OpenTK\GameWindow.cs:line 454
at OpenTK.GameWindow.Run(Double updates_per_second, Double frames_per_second) in C:\Users\Nexrem\Desktop\transfer\opentk\src\OpenTK\GameWindow.cs:line 375
at Vintagestory.Client.ClientProgram.Start(ClientProgramArgs args, String[] rawArgs)
at Vintagestory.ClientNative.CrashReporter.Start(ThreadStart start) in VintagestoryLib\Client\ClientPlatform\ClientNative\CrashReporter.cs:line 93

1: i second the eraser

2: please add mixed colors

3: for glow paint please let it just combine with other colors. (secondary, tertiary, gradient... or even better just type in a color and/or use a wheel)

4: a painting pallete would be really useful as a color wheel selector you can store all your pigments into

5: please add more shapes and textures to work with if possible.

Would really like an eraser. Being able to cover the block to erase the whole face is okay, but as an artist, you gotta erase little bits to make things perfect.