Cavern Background team of ATLAS software developers has organized on-line meeting broadcasting from Stanford University, California, USA. Four teams have been involved into consideration – SLAC from Stanford University, USA; University of Louisville, USA; GCCEC , Tbilisi, Georgia and ATLAS TCn, CERN, Geneva, Switzerland. GCCEC represented results of investigation of Detector geometry in GAP zone between the barrel calorimeter and end cap. It was detected that many of detector components and services are “dropped” into considering zone. Each has been documented as a separate slide in presentation (download .pdf here). 3 groups of services have been separated and corresponding 3D models for 3D interaction was added to pdf. Heavy consideration of founded cases to be followed by US groups. Cavern background software developers express interest to cooperate with GCCEC to develop ATLAS geometry for FLUGG simulation.