Compile error when building Tilengine

[Motherbrain]

This is from main.c in the test project (that I downloaded from github):

Code:

/* test layer */
tilemap = TLN_LoadTilemap("dummy", NULL);
for (c = 0; c < 2; c++)
{
TLN_SetLayer(0, NULL, tilemap);
if (tilemap == NULL)
tilemap = TLN_LoadTilemap("assets/sonic/Sonic_md_bg1.tmx", NULL);
}

The assets folder is in the same folder as the exectuable. I checked to see if the required asset is actually at the expected location and it is.

When I try to step into (F11) TLN_LoadTilemap("assets/sonic/Sonic_md_bg1.tmx", NULL) nothing happens and the process seems to hang.

Not sure why I can't even step into that function using the debugger in VS2019.