That's not how it works for me. Maybe I'm misunderstanding you... I'm starting with no files open in SlickEdit. Open one file. It shows a tab. Zoom the window; now there's no tab showing. I was closing the file, but also now tried going to the menu and choosing Window/Close. Now there's no file window. Open the same file again. I again get a file window with a tab showing. I tried exactly the same thing after starting SlickEdit with a new config (-sc junk) and canceling the config wizard. Same results.
Here is my environment:
SlickEdit 2013 (v18.0.0.6 64-bit)
Serial number: FE11502_BETA
License type: Beta License
License expiration: 2013-07-24 11:46:00
License file: C:\ProgramData\slickedit\18\slickedit.lic
Build Date: May 01, 2013
Emulation: CUA
OS: Windows 7 x64
OS Version: 6.01.7601 Service Pack 1
Memory: 22% Load, 3715MB/16374MB Physical, 3711MB/32746MB Page File, 221MB/8388607MB Virtual
Shell Info: C:\Windows\system32\cmd.exe /q
Screen Size: 2560 x 1440
Project Type: No project open
Language: .txt (Plain Text)
Installation Directory: C:\Program Files\SlickEdit\18.0.0 Beta2\ (non-removable drive,NTFS,189496MB free)
Configuration Directory: c:\Users\bej\Documents\junk\18.0.0\ (non-removable drive,NTFS,189496MB free)
Spill File: C:\Users\bej\AppData\Local\Temp\$slk.0 (non-removable drive,NTFS,189496MB free)