Model design recommendations

Glazings

Model your glazing with a single layer (one thin surface). If it represents a double or triple glazing, keep that into account when you input the transparency (multiply the glazing transparencies of the different layers).
 

Translucent glazings
Model these as normal glazings. When loading your model into Lightsolve, you will be shown a complete list of materials and you'll be able to change the glazing type. Avoid at all costs multiple layers! This is very important for diffusive glazings, because diffusing an already diffuse light beam is as expensive in terms of computation as useless in terms of quality of the result.

Materials and colors
Lightsolve requires each object of the scene be set a material. You can set it by layer, by group, by object or by face, but leave no visible surface with the default gray material. Most probably you'll have at least a transparent and a solid material in your model. You'll be able to better define the materials when loading your model into Lightsolve. 

Surfaces of interest / sensors
You will need to define surfaces in your scene for which you want to compute illuminance and performance. To do so, you can use the existing surfaces in the scene (i.e. a table, the ground, etc) by right clicking it and selecting create the type of sensor you want to create.

If your sensors do not correspond exactly to a surface in your model, it is suggested to model 100% transparent surfaces that you will use specifically when placing sensors. They will be invisible for the simulation and the rendering. In alternative, you will be able to manipulate the sensors after creation, but this operation can be tricky and is not very precise. In principle, Lightsolve is a rendering and performance simulation tool: modeling features are not its key-stength.

Geomerty constraints

Do not design perfectly overlayed surfaces: it is impossible for a ray traversing the geometry to know which surface is hit if two surfaces are at the same position.

Keep in mind that Lightsolve does not only render your models, but it also simulates the light flux in a scene in a physically accurate way. The method is complex in its own, and the pre-computation time is longer the more there are more vertices/faces, so avoid using godzillions of triangles to model furniture and decoration if you want to run a full simulation.