AMS2 - User Livery Overrides

Problem with custom livery for Porsche 991 GT3R: internal banner not showing up.
Maybe someone here can help me. I made a livery for the Porsche 991 GT3R. All is fine, but the internal windscreen banner is not showing up. The “porsche_991_gt3r_dist.xml” defines a 1024x256 DXT5 with MIPs, but the banner template from the” AMS2_Porsche_991_gt3r_2016_template.rar” is 1024x128. I tried both resolutions for the banner.dds, but had no success. In cockpit view in game there is only the black transparent stripe, but no logo.