Sample spinning is available only in the fast-motion limit. Weblab calculates sideband intensities according to Schmidt-Rohr and Spiess in Multidimensional Solid-State NMR and Polymers, page 102). The spinning angle is not restricted to the magic angle and the spinning speed must only be greater than zero.<p>
The calculated sideband intensities are listed on the screen in the output section. Their quality strongly depends on the number of integration steps when integrating over the unit sphere in case of powder samples or part of it in case of oriented samples. This can be adjusted by the quality setting.<p> 
The lower the spinning speed the more sidebands are necessary to represent the spectrum. In principle Weblab can calculate up to 150 sidebands, but in most cases the calculation will stop at much lower values, when sideband intensities are close to zero or because the expected runtime will exceed the limit defined in the prefences.