Tilengine - The 2D retro graphics engine forum

does tilengine output framebuffers of size 400x240 only when using an external renderer, i've gone over the code (granted im very tired at present) but couldnt see any reason why it would do this

No, you can use any framebuffer size when calling TLN_Init(). Just make sure to provide a memory buffer to TLN_SetRenderTarget() that matches the size setted before.