To replicate:
My Preferences > My Account > User Prefererences tab > Verify you are set to MicroTiny WYSIWYG editor.
Layout > Design Manager > Stylesheets tab > Options, create new stylesheet, name it MicroTiny, put simply "color: red;"
Extenstions > MicroTiny WYSIWYG editor > Settings tab > Admin editors > Stylesheet for editor: MicroTiny
Site Admin > Site Maintenance > Cache and content tab > Clear cache
Content > Content Manager > edit a page
I expected to see red text in the WYSIWYG window, I actually see black text on white.
Perhaps I am misunderstanding something?

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Cms Version: 2.1.5
Installed Modules:
AdminSearch: 1.0.2
CMSContentManager: 1.1.1
CMSMailer: 6.2.14
DesignManager: 1.1.1
FileManager: 1.5.2
FormBuilder: 0.8.1.4
LISE: 1.2.1.1
LISELISECharacters: 1.2.1.1
LISEStories: 1.2.1.1
MicroTiny: 2.0.3
ModuleManager: 2.0.4
Navigator: 1.0.3
News: 2.50.5
Search: 1.50.2
Showtime2: 3.5.3
SimpleSiteInfo: 3.1.1
UsersGuide: 2.0
Config Information:
php_memory_limit:
max_upload_size: 32000000
url_rewriting: none
page_extension:
query_var: page
auto_alias_content: true
locale:
set_names: true
timezone: Europe/London
permissive_smarty: false
Php Information:
phpversion: 5.6.24
md5_function: On (True)
json_function: On (True)
gd_version: 2
tempnam_function: On (True)
magic_quotes_runtime: Off (False)
E_ALL: 22519
E_STRICT: 0
E_DEPRECATED: 0
test_file_timedifference: No time difference found
test_db_timedifference: No time difference found
create_dir_and_file: 1
memory_limit: 128M
max_execution_time: 120
register_globals: Off (False)
output_buffering: 4096
disable_functions:
open_basedir:
test_remote_url: Success
file_uploads: On (True)
post_max_size: 32M
upload_max_filesize: 32M
session_save_path: /tmp (1777)
session_use_cookies: On (True)
xml_function: On (True)
xmlreader_class: On (True)
check_ini_set: On (True)
curl: On
Performance Information:
allow_browser_cache: Off (False)
browser_cache_expiry: 60
php_opcache: Off (False)
smarty_cache: Off (False)
smarty_compilecheck: Off (False)
smarty_cache_udt: Off (False)
auto_clear_cache_age: On (True)
Server Information:
Server Software: Apache
Server Api: cgi-fcgi
Server Os: Linux 2.6.18-471.3.1.el5.lve0.8.72 On x86_64
Server Db Type: MySQL (mysqli)
Server Db Version: 5.6.30
Server Db Grants: Found a "GRANT ALL" statement that appears to be suitable
Permission Information:
tmp: /home/cthuk/public_html/storystack/tmp (0755)
tmp_cache: /home/cthuk/public_html/storystack/tmp/cache (0755)
templates_c: /home/cthuk/public_html/storystack/tmp/templates_c (0755)
modules: /home/cthuk/public_html/storystack/modules (0755)
uploads: /home/cthuk/public_html/storystack/uploads (0755)
File Creation Mask (umask): /home/cthuk/public_html/storystack/tmp/cache (0755)
config_file: 0444
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