Here is one of the error reports, perhaps it will be helpful. I have the latest version of tapatalk from the Windows Phone store.
[Type]:[CookieException]
[ExceptionMessage]:[An error occurred when parsing the Cookie header for Uri 'http://www.suscipedomine.com/'.]
[StackTrace]:[
at Tapatalk.Core.Net.WebCall.<MakeHttpCall>d__27.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
at Tapatalk.Core.XmlRpc.XmlRpcClient.<DoXmlRpcCall>d__15`2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
at Tapatalk.Core.UserProxy.<LoginAsync>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
at Tapatalk.ViewModel.VMLoginControl.<LoginCommandExecute>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.AsyncMethodBuilderCore.<ThrowAsync>b__0(Object state)]
[InnerException]:[
[Type]:[CookieException]
[Message]:[The 'Path'='/forum/' part of the cookie is invalid.]
[StackTrace]:[ at System.Net.Cookie.VerifySetDefaults(CookieVariant variant, Uri uri, Boolean isLocalDomain, String localDomain, Boolean set_default, Boolean isThrow)
at System.Net.CookieContainer.CookieCutter(Uri uri, String headerName, String setCookieHeader, Boolean isThrow)]
[InnerException]:[none]]
[OccurrenceDate]:[Sun, 29 Sep 2013 04:50:33 GMT]
[AppInstallDate]:[Sun, 29 Sep 2013 04:48:49 GMT]
[AppTotalRuns]:[1]
[AppRunsAfterLastUpdate]:[1]
[AppVersion]:[1_0_3_13]
[Culture]:[en-US]
[CurrentPageSource]:[/View/VJoinPage.xaml?DirectoryId=58960]
[NavigationStack]:[
/View/VAnonymousPage.xaml?DirectoryId=58960
/View/VTapatalkNetworkSearchPage.xaml
/View/VMainPage.xaml]
[DeviceManufacturer]:[NOKIA]
[DeviceModel]:[RM-820_nam_att_100]
[DeviceHardwareVersion]:[1.0.0.0]
[DeviceFirmwareVersion]:[1232.5962.1314.0001]
[OSVersion]:[Microsoft Windows NT 8.0.10211.0]
[CLRVersion]:[4.0.50829.0]
[DeviceType]:[Device]
[NetworkType]:[Wireless80211]
[DeviceTotalMemory(Mb)]:[898.3867]
[AppPeakMemoryUsage(Mb)]:[38.375]
[AppCurrentMemoryUsage(Mb)]:[30.51953]
[IsoStorageAvailableSpace(Mb)]:[3256]