Here is my first cut at installation instructions for YAF in a subdirectory with MMF. I can't attach a document, so here is the full text in this message. Sorry.

YetAnotherForum.NET (YAF) INSTALLATION FILE
YAF Setup Instructions for sub-site with Microsoft Membership Framework enabled.
STEP 1. UNZIP
Unzip the entire archive to to a folder you want to run YAF in on your web server.
STEP 2. SELECT WEB.CONFIG FILE
If you are upgrading an existing YAF installation please be careful and follow
a few precautions: ALWAYS BACKUP YOUR DATABASE BEFORE ATTEMPTING AN UPGRADE.
IMPORTANT: UPGRADING YAF FORUMS v1.9.1.x and BELOW:
You need to copy and rename the "/webconfigs/v191-upgrade-web.config" to "/web.config" as it
contains necessary settings for the YAF membership providers to support backwards
compatibility with your older YAF database. It's required that you merge these settings
into your existing "web.config" file. If you need to do development with an
upgraded installation, please use "/webconfigs/dev-v191-upgrade-web.config".
A tip to merge web.config files is to download both of them, then use a merge program to
combine. WinMerge is a free and excellent merge program which you can download
here:
http://www.winmerge.org/
IMPORTANT: UPGRADING YAF FORUMS v1.9.3 BETA, RC1 and RC2:
You need to MERGE the changes for the /webconfigs/recommended-web.config or the
/webconfigs/v191-upgrade-web.config depending on the original web config you used -- the
membership provider settings have changed.
NEW INSTALLATION:
If you are starting with a new installation, we recommend you start with
"/webconfigs/recommended-web.config" and copy/rename it to "/web.config."
The "/webconfigs/recommended-web.config" files contains better default
ASP.NET security settings for a NEW installation of YAF.
If you are doing development, use the "/webconfigs/dev-recommended-web.config"
instead.
Please Note: These web.config files will not work if you are upgrading from v1.9.1.x
or below of YAF.
Warning: DO NOT edit the web.config unless you know what you're doing.
STEP 3. SETUP DATABASE (IGNORE IF UPGRADE)
A existing database needs to exist on your SQL Server with proper permissions
set so that YAF can access it. When you run YAF for the first time it will
detect that the database is empty (or needs upgrading) and will automatically
run you through the process required to create the SQL database structures
needed.
STEP 4. MODIFY DB.CONFIG FILE:
Modify the yafnet connectionString property to use your SQL Server database.
The database must exist on the server with proper permissions, but it can be
empty. Need help with your connection string? Visit this url:
http://www.connectionstr....aspx?carrier=sqlserver
Look under the heading for "SqlConnection (.NET)" for example connection strings.
STEP 5. Relocate /bin and /App_Code to webroot.
By default YAF is designed to be installed at the root application on any
IIS web server. If you want YAF to be installed off of the main root, you need
to modify the root key.
In order for YAF to function in a sub-directory, the contents of the /bin directory
and the /App_Code directory need to be copied to the root of your website application.
In addition you will need to copy the App_Code folder to the root of your website.
STEP 6. MODIFY "app.config" FILE:
Then open up "app.config" and uncomment the "root" key. Enter the value as the
directory to your forum.
Example: If you have install the forum in the directory "/forum/yaf/"
you will need to add key with name "root" and value "/forum/yaf/"
to app.config. Here is an example where the forum is in a sub-directory
called "forums". <add key="YAF.Root" value="/forums/"/>
You will also have to change your BaseURL setting to reflect the location of your
forum. For example, if your forums are in <webroot>/forums, you would change the
BaseURL key to <add key="YAF.BaseUrl" value="~/forums" />.
Also, in "app.config" you can modify the BoardID to use the board you want.
If you only have one board or don't know what this is, leave it alone.
STEP 6a.
If you are using the Microsoft Membership Framework on your root website application,
your root web.config will have settings for Role Manager and Provider. These settings
will conflict with the default YAF settings in the YAF web.config. Therefore you will
need to open the YAF web.config and comment out or remove the following sections.
<!-- This is the original YAF configuration for roles.
<roleManager enabled="true" defaultProvider="YafRoleProvider">
<providers>
<clear/>
<add connectionStringName="yafnet" applicationName="YetAnotherForum" name="YafRoleProvider" type="YAF.Providers.Roles.YafRoleProvider"/>
</providers>
</roleManager>
<membership defaultProvider="YafMembershipProvider" hashAlgorithmType="SHA1">
<providers>
<clear/>
<add connectionStringName="yafnet" applicationName="YetAnotherForum" name="YafMembershipProvider" requiresUniqueEmail="true" useSalt="true" type="YAF.Providers.Membership.YafMembershipProvider"/>
</providers>
</membership>
<profile enabled="true" defaultProvider="YafProfileProvider" inherits="YAF.Classes.Utils.YafUserProfile">
<providers>
<clear/>
<add connectionStringName="yafnet" applicationName="YetAnotherForum" name="YafProfileProvider" type="YAF.Providers.Profile.YafProfileProvider"/>
</providers>
</profile>
-->
STEP 7. (OPTIONAL) MODIFY "mail.config" FILE:
Modify the smtp settings by entering your mail server information.
STEP 8. NEW INSTALLATION:
Open the file <YAFroot>install/default.aspx on your web site. If you
are testing on your local computer, under a directory called
YetAnotherForum.Net, the address should be:
http://localhost/yetanotherforum.net/install/
Follow the installation wizard directions and you should be able to log
in with the administration account you created during the setup.
Give the ASPNET/Network Service account write access to the Upload
folder.
STEP 9. UPGRADE:
Open the file <YAFroot>install/default.aspx on your web site. If you
are testing on your local computer, under a directory called
YetAnotherForum.Net, the address should be:
http://localhost/yetanotherforum.net/install/
The wizard will guide you through the upgrade process.
If you have any questions, please visit the YAF Support forum:
http://forum.yetanotherforum.netWe'll be happy to help. But please remember YAF is supported by volenteers.
YAF Support (support@yetanotherforum.net)