Updated FAQ section

FAQ.md

@@ -22,9 +22,11 @@ I have succesfully tested the following OPDS-Reader:
 - Marvin and Marvin3 on iOS\
 - Calibre-companion on Android (Book downloads viewing book details are also supported with this reader even it's not using the standard opds features)\
 - Kybook 1/2/3 on iOS\
-- Megareader on iOS (download seems not to work)
-- moon+ on Android
-- ebookdroid on Android
+- Megareader on iOS (download seems not to work)\
+- moon+ on Android (Cover pictures are only displayed with anonymous browsing enabled, tested with v4.5.7)\
+- ebookdroid on Android (Download is only working with anonymous browsing enabled, tested with v2.6.3)
+- Coolreader on Android (Cover pictures are not supported, tested with v3.2.29-1)
+- FBReader on Android (Cover pictures are only displayed with anonymous browsing enabled, tested with v3.0.8)
 
 I'm not using all the reader regulary, so issues might apear from time to time. If it's reported I'll try to fix it.
 
@@ -94,12 +96,31 @@ I case you entered invalid key files for accessing calibre-web through https, th
 
 Shelfs can be filled book by book on the corresponding detail page. Books can be massadded from the result of an adavned search. Third option for adding many books at one time to a shelf is using a script like the [cps-mass-adder script](https://github.com/OzzieIsaacs/cps-shelf-adder). The order of books in a shelf can be rearranged on the shelf edit page via drag 'n drop. 
 
+
 ### Send to kindle with guest account
 
 In a one user use case you can use the guest account for sending ebooks to kindle. Please add in this case a kindle-email to the guest account, afterwards the "send to kindle" button appears for the guest user. If more than one user is accessing the guest account this is not working, as you can only have one kindle-email linked to a user.
 
+
+### Error on Startup: "the STRING opcode argument must be quoted"
+
+If the calibre-web repro is cloned via git and certain git setting are set (line endings conversion), this could cause this error. The cause is that the line endings in the file cps/translations/iso639.pickle are converted to "windows" endings. To solve the problem, please replace the file with the version from:\
+https://raw.githubusercontent.com/janeczku/calibre-web/master/cps/translations/iso639.pickle\
+or\
+open the file with a advanced editor like notepad++ and change the line endings to Unix -> only LF\
+
+
 ### Link Read Status to calibre custom column
 
+In a single user Calibre installation you can use a boolean custom column to keep track of your read and unread books. Calobre-web can do the following. You can link the Calibre status to the read/unread status in Calibre-Web. As mentioned above this only works in a SINGLE USER use-case. If you are having more than one user in Calibre-Web this will cause trouble, because the read/unread status is than used for all users, so if one user ticks a book as read, all users will see this book as read. In a multiuser Calibre-Web use case it's aboslutly manatory not to use this feature.\
+How to use the feature?\
+1. Open Calibre (the Desktop program) and create a boolean custom column name it accordingly (e.g. Read Status)\
+2. Calibre will ask you for a restart to apply the change. Afterewards please close Calibre\
+3. For safety reasons it's recommended to restart Calibre-Web\
+4. Log in to Calibre-Web as admin and go to Admin->UI configuration->View Configuration\
+5. The field "Link read/unread status to Calibre column" should now offer a selection of all bolean custom columns of the corresponding Calibre library, select the appropriate entry and save\
+The read/unread status is now identical in Calibre and Calibre-Web
+ 
 
 ### How to handle Multiple calibre-libs
 
@@ -107,6 +128,6 @@ In a one user use case you can use the guest account for sending ebooks to kindl
 ### Registering
 
 
-### Concurrent access (calibre and calibre-web)
+### Concurrent access (Calibre and Calibre-Web)