SQL Stairstep Query

Since you are using SQL Server 2012, we can use the Format function to make the date pretty. There is no need to group by the strings. Instead, I find it useful to use the proper data type for as long as I can and only use Format or Convert on display (or not at all and let the middle tier handle the display).

In this solution, I arbitrarily assumed the earliest TransDate and extract from it, the first day of that month. However, one could easily replace that expression with a static value of the start date desired and this solution would take that and the next 12 months.

With SubmissionMonths As
  (
  Select DateAdd(d, -Day(A.SubmissionDate) + 1, A.SubmissionDate) As SubmissionMonth
    , A.Amount
  From dbo.Accounts As A
  )
  , TranMonths As
  (
  Select DateAdd(d, -Day(Min( T.TranDate )) + 1, Min( T.TranDate )) As TranMonth
      , 1 As MonthNum
  From dbo.Accounts As A
    Join dbo.Trans As T
      On T.AccountId = A.AccountId
    Join SubmissionMonths As M
      On A.SubmissionDate >= M.SubmissionMonth
        And A.SubmissionDate < DateAdd(m,1,SubmissionMonth)
  Union All
  Select DateAdd(m, 1, TranMonth), MonthNum + 1
  From TranMonths
  Where MonthNum < 12
  )
  , TotalBySubmissionMonth As
  (
  Select M.SubmissionMonth, Sum( M.Amount ) As Total
  From SubmissionMonths As M
  Group By M.SubmissionMonth
  )
Select Format(SMT.SubmissionMonth,'yyyy-MM') As SubmissionMonth, SMT.Total
  , Sum( Case When TM.MonthNum = 1 Then T.TranAmount End ) As Month1
  , Sum( Case When TM.MonthNum = 2 Then T.TranAmount End ) As Month2
  , Sum( Case When TM.MonthNum = 3 Then T.TranAmount End ) As Month3
  , Sum( Case When TM.MonthNum = 4 Then T.TranAmount End ) As Month4
  , Sum( Case When TM.MonthNum = 5 Then T.TranAmount End ) As Month5
  , Sum( Case When TM.MonthNum = 6 Then T.TranAmount End ) As Month6
  , Sum( Case When TM.MonthNum = 7 Then T.TranAmount End ) As Month7
  , Sum( Case When TM.MonthNum = 8 Then T.TranAmount End ) As Month8
  , Sum( Case When TM.MonthNum = 9 Then T.TranAmount End ) As Month9
  , Sum( Case When TM.MonthNum = 10 Then T.TranAmount End ) As Month10
  , Sum( Case When TM.MonthNum = 11 Then T.TranAmount End ) As Month11
  , Sum( Case When TM.MonthNum = 12 Then T.TranAmount End ) As Month12
From TotalBySubmissionMonth As SMT
  Join dbo.Accounts As A
    On A.SubmissionDate >= SMT.SubmissionMonth
      And A.SubmissionDate < DateAdd(m,1,SMT.SubmissionMonth)
  Join dbo.Trans As T
    On T.AccountId = A.AccountId
  Join TranMonths As TM
    On T.TranDate >= TM.TranMonth
      And T.TranDate < DateAdd(m,1,TM.TranMonth)
Group By SMT.SubmissionMonth, SMT.Total

SQL Fiddle version

The following query pretty much returns what you want. You need to do the to operations separately. I just join the results together:

 select a.yyyymm, a.Amount,
        t201201, t201202, t201203, t201204
 from (select LEFT(convert(varchar(255), a.submissiondate, 121), 7) as yyyymm,
              SUM(a.Amount) as amount
       from Accounts a
       group by  LEFT(convert(varchar(255), a.submissiondate, 121), 7) 
      ) a left outer join
      (select LEFT(convert(varchar(255), a.submissiondate, 121), 7) as yyyymm,
              sum(case when trans_yyyymm = '2012-01' then tranamount end) as t201201,
              sum(case when trans_yyyymm = '2012-02' then tranamount end) as t201202,
              sum(case when trans_yyyymm = '2012-03' then tranamount end) as t201203,
              sum(case when trans_yyyymm = '2012-04' then tranamount end) as t201204
       from Accounts a join
            (select t.*, LEFT(convert(varchar(255), t.trandate, 121), 7) as trans_yyyymm
             from trans t
            ) t
            on a.accountid = t.accountid
       group by LEFT(convert(varchar(255), a.submissiondate, 121), 7)
      ) t
      on a.yyyymm = t.yyyymm
 order by 1

I am getting a NULL where you have a 0.00 in two cells.