Many SDE CAD Client layers and "old style" SDE annotation layers cannot be viewed in ArcCatalog or ArcMap.
Most SDE CAD Client layers have multiple entity types (point, line, or poly). Also, most "old style" SDE annotation layers often contain annotation with both line and point placement features.
SDE CAD Client:
Option 1: Store the CAD layer as multiple SDE layers (point, polygon, line, and anno/point). Note that these layers would need to be edited under different RDBMS transactions. That means that if the store operation fails in the middle, it would be difficult to determine what got stored and what didn't without some detective work; thus, the recovery could be difficult.
Option #2: Store the CAD layer as a heterogeneous SDE layer containing points, polygons, lines, etc. Then, run a nightly batch job that copies the CAD client layer out into 3 or more separate homogeneous SDE layers so ArcCatalog and ArcMap can see them.
Before loading coverage annotation into an SDE layer, rotate the annotation a millionth of a degree. This will force all annotation to use lines instead of points as the placement feature.
Enhancements are being considered to eliminate the need for workarounds.