Trying to set custom projection for shapefile in QGIS

Question

I'm trying to open and use a dataset (in the form of a shapefile) (https://webarchive.iiasa.ac.at/Research/FOR/forest_cdrom/data/landscapes/landscapes.zip) with QGis. The readme of the dataset says following about projection:
Projection: Lambert Azimuthal
Units: Meters
Datum: None
Parameters:
6370997.24063 (radius of the sphere of reference)
100 0 0.000 (longitude of center of projection)
45 0 0.000 (latitude of center of projection)
0.00000 (false easting (meters))
0.00000 (false northing (meters))

I tried to create a custom CRS with the following parameters:
+proj=laea +lat_0=45 +lon_0=100 +x_0=0 +y_0=0 +ellps=GRS80 +r=6370997.24063 +units=m +no_defs
With this custom CRS applied to the dataset it looks shifted along the basemap.
Am I wrong with the projection string? (I also tried to change ellipsoid to 'sphere', without visible improvements.)

Gabriel De Luca · Answer

The radius parameter must be +R instead of +r, but the +ellps takes precedence over +R, so in any case don't use +ellps because the information says that the projection is a conversion from the sphere.
The proj string must be:
+proj=laea +lat_0=45 +lon_0=100 +x_0=0 +y_0=0 +R=6370997.24063 +units=m +no_defs +type=crs
Also, take into account (from https://webarchive.iiasa.ac.at/Research/FOR/forest_cdrom/data/landscapes/readme.txt):

Data Limitations
Differences will occur between among the spatial datasets found here in terms of resolution and scale. In particular, the outer boundary of Russia, islands and waterbodies may vary between datasets. In addition, geo-registration is sometimes problematic with these datasets. As these datasets are derived from a variety of sources, it was not possible to control consistency.

Rudy Stricklan · Answer

Your project parameters are valid, I just tried them. The problem is in some of the other *General projections-- they all need to be deleted until your CRS System Definition screen looks like this:

I arbitrarily named your custom CRS 'Custom'.

Trying to set custom projection for shapefile in QGIS

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