MapComp imposes certain limits on the sizes of various parameters of the files created. These limits are documented here.
Maximum number of descriptors: 100. The maximum number of descriptors which can be created in the output file (which corresponds to the number of object commands in the .MAP file).
Maximum descriptor data size: 60 000 bytes. The maximum amount of data which can be stored for each descriptor (containing line end point positions, turn point positions and name text, and so on).
Generally speaking you should avoid data for descriptors reaching anything close to this limit. The smaller the data for each descriptor the faster the displayer can process it particularly if much of the data lies outside the screen area. If you find you have a descriptor with large quantities of data consider spliting it into two or more separate descriptors based on geographical region.
Minimum arc and circle radius: 0.1nm. Arcs and circles should not have a radius of less than one tenth of a nautical mile.