I'm having a slightly different error, and one which is probably just something simple I'm overlooking.
I'm trying to use the Manifold Image Servers, however whenever I try to add one I just get a blank image. Even if I try to add one that was previously set up and works okay (and, when I go into the properties, has the exact same properties as the one that works).
I've downloaded the dlls (unblocked etc, just as described). This is for Manifold 8 on a 64-bit Win 10 machine. My replication steps are:
* in Manifold, go to File > Link > Images
* then browse for Manifold Image Servers()
* select the service I want (in this case it was Bing, at http://ecn.t*.tiles.virtualearth.net/tiles/ - which does work in a file created before I started in this role)
* choose "global" (already selected) and refresh to ensure it is there. No issues, map size appears
* choose ok. Mapnik is created
From there, if I double-click the mapnik itself, all I get is the standard transparent "checkerboard". This also won't appear on a map if I add it (drag and drop to map), or if I create a new map from it (right-click, create - map). The original one, which does work, works fine in this.
I'm essentially trying to get the OpenStreet Map working, using the .de address, in the end, but practicing using something that should work.