Yes, I see the problem in the Java code. When Render calls all specialized Render functions, it begins with a call to updateAnimationBaseTime. This function is in my code but not made public in the XML file of the library. You have to call it with the JavaObject lib (JO = yourAnimedMapTile, JO.RunMethod("updateAnimationBaseTime", null)) before calling RenderTileLayer.
Sorry for the inconvenience. It seems that the bug is also in the original lib.