diff --git a/libretroshare/src/ft/ftchunkmap.cc b/libretroshare/src/ft/ftchunkmap.cc
index 1efa008a9..5ed39703e 100644
--- a/libretroshare/src/ft/ftchunkmap.cc
+++ b/libretroshare/src/ft/ftchunkmap.cc
@@ -65,16 +65,17 @@ void Chunk::getSlice(uint32_t size_hint,ftChunk& chunk)
 	_offset += chunk.size ;
 }
 
-ChunkMap::ChunkMap(uint64_t s)
+ChunkMap::ChunkMap(uint64_t s,bool availability)
 	:	_file_size(s),
-		_chunk_size(CHUNKMAP_FIXED_CHUNK_SIZE) // 1MB chunks
+		_chunk_size(CHUNKMAP_FIXED_CHUNK_SIZE), // 1MB chunks
+		_assume_availability(availability)
 {
 	uint64_t n = s/(uint64_t)_chunk_size ;
 	if(s% (uint64_t)_chunk_size != 0)
 		++n ;
 
 	_map.resize(n,FileChunksInfo::CHUNK_OUTSTANDING) ;
-	_strategy = FileChunksInfo::CHUNK_STRATEGY_STREAMING ;
+	_strategy = FileChunksInfo::CHUNK_STRATEGY_RANDOM ;
 	_total_downloaded = 0 ;
 	_file_is_complete = false ;
 #ifdef DEBUG_FTCHUNK
@@ -355,13 +356,11 @@ uint32_t ChunkMap::getAvailableChunk(const std::string& peer_id,bool& map_is_too
 	{
 		SourceChunksInfo& pchunks(_peers_chunks_availability[peer_id]) ;
 
-		bool assume_availability = !(rsTurtle!=NULL && rsTurtle->isTurtlePeer(peer_id)) ;
-
 		// Ok, we don't have the info, so two cases:
 		// 	- peer_id is a not a turtle peer, so he is considered having the full file source, so we init with a plain chunkmap
 		// 	- otherwise, a source map needs to be obtained, so we init with a blank chunkmap
 		//
-		if(assume_availability)
+		if(_assume_availability)
 		{
 			pchunks.cmap._map.resize( CompressedChunkMap::getCompressedSize(_map.size()),~(uint32_t)0 ) ;
 			pchunks.TS = 0 ;
diff --git a/libretroshare/src/ft/ftchunkmap.h b/libretroshare/src/ft/ftchunkmap.h
index 46a088c6f..7b79259fd 100644
--- a/libretroshare/src/ft/ftchunkmap.h
+++ b/libretroshare/src/ft/ftchunkmap.h
@@ -92,10 +92,7 @@ class ChunkMap
 
 		/// Constructor. Decides what will be the size of chunks and how many there will be.
 
-		ChunkMap(uint64_t file_size) ;
-
-		/// constructor from saved map info
-		ChunkMap(uint64_t file_size,const std::vector<uint32_t>& map,uint32_t chunk_size,uint32_t chunk_number,FileChunksInfo::ChunkStrategy s) ;
+		ChunkMap(uint64_t file_size,bool assume_availability) ;
 
 		/// destructor
 		virtual ~ChunkMap() {}
@@ -184,6 +181,7 @@ class ChunkMap
 		std::map<std::string,SourceChunksInfo>		_peers_chunks_availability ;	//! what does each source peer have
 		uint64_t												_total_downloaded ;				//! completion for the file
 		bool													_file_is_complete ;           //! set to true when the file is complete.
+		bool													_assume_availability ;			//! true if all sources always have the complete file.
 };
 
 
diff --git a/libretroshare/src/ft/ftcontroller.cc b/libretroshare/src/ft/ftcontroller.cc
index 41e12d856..79264dbe4 100644
--- a/libretroshare/src/ft/ftcontroller.cc
+++ b/libretroshare/src/ft/ftcontroller.cc
@@ -1200,7 +1200,9 @@ bool 	ftController::FileRequest(const std::string& fname, const std::string& has
   	if(flags & RS_FILE_HINTS_NETWORK_WIDE)
 		mTurtle->monitorFileTunnels(fname,hash,size) ;
 
-	ftFileCreator *fc = new ftFileCreator(savepath, size, hash);
+	bool assume_availability = flags & RS_FILE_HINTS_CACHE ;	// assume availability for cache files
+
+	ftFileCreator *fc = new ftFileCreator(savepath, size, hash,assume_availability);
 	ftTransferModule *tm = new ftTransferModule(fc, mDataplex,this);
 
 #ifdef CONTROL_DEBUG
diff --git a/libretroshare/src/ft/ftfilecreator.cc b/libretroshare/src/ft/ftfilecreator.cc
index 32c5b480f..fe14ee871 100644
--- a/libretroshare/src/ft/ftfilecreator.cc
+++ b/libretroshare/src/ft/ftfilecreator.cc
@@ -17,8 +17,8 @@
 *
 ***********************************************************/
 
-ftFileCreator::ftFileCreator(std::string path, uint64_t size, std::string hash)
-	: ftFileProvider(path,size,hash), chunkMap(size)
+ftFileCreator::ftFileCreator(std::string path, uint64_t size, std::string hash,bool assume_availability)
+	: ftFileProvider(path,size,hash), chunkMap(size,assume_availability)
 {
 	/* 
          * FIXME any inits to do?
@@ -539,7 +539,9 @@ bool ftFileCreator::crossCheckChunkMap(const CRC32Map& ref,uint32_t& bad_chunks,
 				else
 				{
 					printf(" cannot fseek!\n") ;
-					return false ;
+					++bad_chunks ;
+					++incomplete_chunks ;
+					map.reset(i) ;
 				}
 			}
 			else
diff --git a/libretroshare/src/ft/ftfilecreator.h b/libretroshare/src/ft/ftfilecreator.h
index 1048fa7c7..7915d95ae 100644
--- a/libretroshare/src/ft/ftfilecreator.h
+++ b/libretroshare/src/ft/ftfilecreator.h
@@ -40,7 +40,7 @@ class ftFileCreator: public ftFileProvider
 {
 	public:
 
-		ftFileCreator(std::string savepath, uint64_t size, std::string hash);
+		ftFileCreator(std::string savepath, uint64_t size, std::string hash,bool assume_availability);
 
 		~ftFileCreator();